Acom Internet User Guide

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Introduction Acom Internet Background How do I get an Internet connection?

Setting up Modem Configuration instructions

Configuring the Internet server Setting up communications functions

Configuring IMail Installing !Mail Setting the Post_In and Post_Out directories

Configuring the Web browser Page caches Browser configuration Network configuration

Managing the mail server Setting up users and user groups Managing newsgroups Allowing and disallowing Web URLs N^l statistics L flaying the server log Finger Quitting Connea Saving space

Using Mail Starting IConnect Connecting with the mail system Sending mail Reading mail Forwarding a mail message Connecting with the Internet Logging off and Quitting

Using the Web browser Starting the Web browser Overview Finding>starting and stopping links The browser menu Viewing locally-stored pages

Using news Reading news Forwarding an article by email Following up an article Replying to an article (by email) Saving an article Starting a new thread

Playing other multimedia data types BWing Java applets ISnbckwave

World Wide Web pages What are Web pages? Creating Web pages Identifying resources - URLs Serving pages

AppendixA: Acronyms and Smilies Acronyms Smilies ^pendix B; Writing Acorn Internet Command Scripts Ii>. oduction Protocols and Interfaces Anatomy of a logon script Writing your Own Scripts Handling Dynamic IPAllocation Scripting Language Conunand Set pppconnect for RISC OS Authentication Routing Bibliography

Appendix C; Glossary

Copyright notices Copyright © 1995,1996,1997,1998 Acom Computers Limited. All rights reserved. No part ofthis publication may bereproduced ortransmitted, in any form orbyany means, electronic, mechanical, photocopying, recording orotherwise, or stored in any retrieval system of any nature, without thewritten permission ofthecopyright holder and thepublisher, application forwhich shall be made to the publisher. Theproduct described inthismanual is notintended for use as a critical component in lifesupport devices or any systemin whichfailure could be expectedto result in personalinjury. Theproduct described inthismanual is subject to continuous development and improvement. All information of a technical nature and particulars of theproduct and its use (including the information and particulars in this manual) aregivenbyAcomComputers Limited in good faith. However, Acom Computers Limited cannot accept anyliability for anyloss ordamage arising from the use of any information or particulars in this manual. If you have anycomments onthis manual, please complete the form at thebackofthe manual and send it to the address given there. Ag^m supplies its products through an intemational distribution network. Your supplia* is available to help rcoolve any queries you might have. Within this publication, the term^BBCis used as an abbreviation for ^British Broadcasting Corporation'. ACORN,the ACORN logo, ARCHIMEDES and ECONETare trademarks of Acom Computers Limited. All other trademarks are acknowledged.

Published by Acom Computers Limited Part Number 0484,854 Issue C, January 1998 1 Introduction

Acorn Internet

Acom Internet software gives you eveiythingyou need to browse the World Wide Web, send and receive email, and read and participate in global newsgroups.

Controlling access and costs

Acom Intemet software is easy to configure and to use. Great emphasis has been placed on control and observation,to ensure that users have access only to approved newsgroups, email addresses and Webpages.

AcornIntemet software also helps you controltelephoneline costs, with frequency and lengthof connection being fully configurable. Reports on coimect times, news and email volume are available to the qw at any time. Background

What Is the Internet?

The Intemet is a global network of networks, with tens of millions of users world wide. It covers a wide range of services - electronic mail (email), bulletin boards, newsgroups, file transfer, remote logon and the World Wide Web.

The World Wide Web is a hypermedia-linked information server system which can handle "pages' of text, pictures and even audio. This entire network of pages can be potentially interlinked, with bnks on one page bringing related information that's on another page. Sitting at your computer, you can bring one page to y^r computer screen from a computer in Australia, read its contents, and then by clicking a mouse button, biiiig more pages of related information from a computer in Alaska. You traverse the Intemet by moving from one page to another via links - this is what is meant by surfing the net.

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Of the range of Internet services, AcornInternetsoftware provides the main ones- email, news and a Web ^browser'.

The origins of the Internet

The origins of Intemet go back to the mid-seventies, out of a need to connecttogetherthe US Defense Department ARPAnet and variousother radio and satellitenetworks. Withnuclearwar in mind, it had to be as tolerant of network breakdowns as possible, so was set up as a "peer-to-peer'network - each computer communicating with every other one as an equal. Data was sent in hitemet Protocol (IP) packets, addressed to the destination machine.

same IP networking software came with Berkeley UNIX workstations, which proliferated in Local Area Networks in the eighties. It soon became clear that these local networks could be connected to the ARPAnet, so that every workstation on a site could access ARPAnet facilities.

In the late eighties, the National Science Foundation (NSF) set up five supercomputer centres in the United States, and every university was connected to these centres via its own regional network. This NSFNET provided the basis of the present-dayIntemet network in the US, to which networksin the UnitedKingdom and other countries are connected. NSFNET, NASA Science Intemet and other US federal agency networks recently joined forces to form the National Research and Education Network (NREN).

The Intemet was originally used by universities, research establishments, companies and govemment departments to communicate with each other and share resources. Increasingly, though, private subscribers are joining, via a growing number of service providers.

core ofthe Intemet is a TCP/IP network, but many other non-IP networks (such as Acom Econet, BITNET and DECnet) have found ways to coimect to it. This means that almost anyone with a computer can join it, either via a gateway between their own network and the Intemet, or by leasing an account on a computer with a full connectionto the Intemet, and communicating via that computer, using a modem and telephone line. "The Intemet' has therefore come to mean not just the original TCP/IP network, but the global ccMnmunity of disparate interconnected computers.

What is the World Wide Web?

The World Wide Web (also known as WWW, W3 or simply "the Web") attempts to oiganise information on the Intemet as a set ofhypertext or hypermedia documents.

In a hypertext document,if you want more information about a particularsubjectmentioned, you just click your mouse buttonover a highlighted wordor pictureto bring another, linkedpage of information to your screen. Hypermedia links will not only bring you a page to read but also bring images, and play video and sound clips - all at the click of your mouse button. Most pages on the WorldWide Web provide these built-in links to other pages.

If all the early running in developing the Internet was made in the United States, the development of the WorldWideWeb has been a truly internationalphenomenon. It began as a networkedinformationproject of EnglishmanTim Bemers-Lee at CERN (the EuropeanLaboratoryfor Particle Physics in Switzerland) in 1989.The aim was to build a distributed hjrpermedia system, that is, a system where information of interest to the scientific research community and in different file formats- text, pictures, movies, and so on - was stored across many different computers in different locations, and which could be accessed by pointing and clicking.

Once a graphical interface for the Web, Mosaic, was developed by the National Centre for Supercomputing Applications (NCSA) in Illinois, the project rapidly grew to cover more and more resources, computers and users across the Internet. In January 1993, there were just 50 WorldWide Web servers world-wide: by October 1993 this number had grown to 500. Currently, there are over 1000 World Wide Web servers in the UK alcMie.

Who controls the Internet?

The Internet is not run by one company, although some corporate networks that form part of it may be. There is a voluntary body, called the Internet Society (or ISOC), which appoints a council ofelders responsible for the technical management and direction ofthe Internet. But generally speaking the Internet is an informal, self-governing community. As in any social group, if members behave badly, the others shun them or let them know what they think about it.

Your company or school may have its own Internet rules. Find out what they are, and be sure to follow them.

There are a few general rules, however, that you should be aware of:

Ommercial use

When you join the Internet, you may be asked ifyour intended use is Commercial, or Research and Education. Ifthe latter, your calls may be routed in the US over subsidised federal NSFNET routes, rather than more expensive commercial ones. Research and Education users, therefore, should not subsequently engage in commercial activities over the Internet.

Even amongst company users, there is stiQ a lot of feeling against blatant commercialism on the Internet. The ability to find out about commercialproducts is a good thing, and WorldWide Webpages are particularly useful for this purpose, but most users do not want to be bombarded with unsolicited promotions.

Legal issues

Through the Intemetyou can have access to information andproducts whichare the result of personal, public orcommercial research and development. Before you use these for your own purposes, make sure that you obtain any necessary permissions to do so.

TheInternet is international, so anything you send could go anywhere in the world. Sending datato another country is considered to be exporting. Exporting any restricted information or product, or granting access to a supercomputer or sensitive database over theInternet may require anexport licence. Usually, information that is available to the general publicis not considered to be restricted, but information available in universities, government departments and companies may be. If in doubt, seeklegal advice. Network ethics and ^Netlquette'

Becausethe Internet is so openand comparatively unfettered, it is also open to abuse. The mainthreatsto the Internet are

excessive use for unintended purposes political pressures.

The two are linked. If your employer or schoolis payingfor your Internet connection, they will not take kindly to you participating in an all-daymulti-usercomputergame over the Internet. Even if you are paying for your own connection,parts of the Internet (NSFNET, for example) are state-subsidised, and should not be abused in this way. If they are, there will be political pressure to cut the subsidy.

The same goes for personal attacksand rude and antisocialbehaviour, and making obscenefiles available over the Internet.If this happens too often,those who pay for Internet will either withdraw funding, or impose restrictive controls on the network which reduce its effectiveness and ease of use.

If these very reasonable restrictionsare borne in mind, the Internet is a very liberal environment,where individualism and self-expression are encouraged.

Once you are connectedto the Internet,you can get some useful guidance on Internetbehaviourfrom the nOsgroup news.announce.newusers, including Frequently-Asked Questions (FAQs). (See the appendix Acronyms and Smilies for more information on net-speak.) How do I get an Internet connection?

You should contact one ofthe Internet service providers. For a fee (usually a monthly payment) they provide a connection to the Internet, via a UK telephone number which your computer dials up using a modem. Many ofthe service providers offer local rate calls, so that you can communicate over Internet anywhere in the world, and still pay local charges.

When you are connected to the Internet, you can send and receive electronic mail and access news on bulletin boards.

Internet service providers These are someof the best-known service providers for the homeandeducation user at the time of writing:

Demon Internet

Telephone: 0181 371 1234

Lx)cal access nation-wide (including loW and loM)

Email address: [email protected]

Web: http://www.demon.net/

Pipex (UUNET UK)

Telephone: 01223 250120

Local access in most areas

Email address: [email protected]

Web:http://www.pipex.com/

Zynet

Telephone: 01392 209500

Local access in most areas

Email address: [email protected]

http://www.zynet.co.uk/

Many of these organisations are growing, and may have more access points (^points of presence*) by the time you read this.

Other providers supported by Acom Internet software at the time of writing are:

Aladdin Argonet Bournemouth Colloquium Dorset Dungeon Frontier Pavilion Poptel Power Pronct RMplc. What you shouici get

Your service provider acts as a gateway between youandthe Internet, and may alsoofferadditional facilities that you can make use of, such as security,censorship or even separate on-line services.

Your providerwillprobably be ableto offeryou a choiceof options and services, so that you can choose the type of account that suits you best. Some of these choices may be:

ISDN or telephone connection l^N is more costly, but gives better response, and isa serious option for a medium tolaige networked site. \uu will need to purchase an ISDN router. Ifyou have one of these, you will be allocated a static DP address, so you can take advantage of SMTP mail delivery (see below).

SLIP or PPP

These are means of communicating down a telephone line to provide a connectionbetween the provider and your server machine. SLIP is simple,but rather outdated;PPP is more secure and can be faster. SLOP software is not provided with Acorn Internet, but can be obtained from Gnome Computers ifrequired.

SMTP or POPS

SMTP and POP are means of downloading mail stored temporarily by your provider. SMTP aUows the mail for a whole site to be downloaded into the mail server machine in one go. P0P3 is intended for single users a^mail is read directly from your provider.

SMTP requires a static IP address to be aUocated to you, and these are becoming increasingly difficult to obtain.

Static or dynamic IP address allocation

Ifyou wish to serve web pages from your site (see Serving pages), you wiUneed to purchase a service that gives you a static address, so that others outside know how to find you. Otherwise, a dynamically-allocated address is adequate. This means that every time you dial up, you wiDbe aUocateda temporary IP address for that session. As mentioned earlier, you can only make use of SMTP delivery ifyou have a static DP address.

Name server For web access, you should use a 'name server* that can translate web requests fix)m the web-server name to its equivalent IP address. Your local provider should be able to provide details of this service.

Web cache Web pages tend to contain a lot of data, so take a comparatively long time to load. There is consequently a benefit to "cache' (store) frequently-used web pages locally,to cut down access times and net traffic. Acorn Internet software provides a cache for your server machine, and service providers may also offer caches on their servers, known as proxy caches, to which you can direct your own cache - to give an even better Web response.

Pop When you have chosen the type of service appropriate for your needs, your provider will then advise you of the nearest PoP (point of presence) which should be a local charge number.

Hostname will agree with your provider a unique host name and password for your account.

The host name, or Internet address, that people will use to send mail to you, takes the form of [email protected]_provider_address for example: plug @bashstrt demon.co.uk user Host name service provider

You can fill in details of your chosen provider in the table below for quick reference:

Service provider Chile ODim Location Telephone number SMTP/P0P3

Hostname

Password Web proxy address

Nameserver Static / dynamic IP SLIP/PPP/ISDN 2 Setting up

Modem

Which modem to get

You will need a modem, to convert the digital signals output by the computer to the analogue signals required for transmission across telephone lines. Modems should operate V.32 bis or V.34 protocols, at a minimum rate of 28,800 baud. A 33,600 baud modem is even better.

Slower, older, modems will prove expensive to run, as the time taken to transfer data will be longer, and your telephone bill correspondingly higher.

There is a list of modems displayed by the configuration software (see Modem configuration) which have b^n tested with Acorn Internet software. This list is not intended to be exhaustive, nor is inclusion in it Ux^ended to imply approval by Acorn.

Connecting up the modem

Connect the modem to the serial port of the Acorn computer you will be using as the mail server.The Rise PC uses a standard PC modem cable, while your supplier will tell you which cable to use for earlier Acorn computers.The telephone connection for the modem plugs into the normal telephone wall socket.

You should be able to use the factory settings on the modem. Check the Release Note for any particular items to note when operating modems. Configuration instructions

Configuration requires some care, as different Internet Service Providers (ISPs) requiredifferent settings. As a guide, we have provided example configurations in the form ofcompleted dialogue boxes for the three main types ofconnection. You can use these examples to help you complete the configuration dialogue boxes in the next few chapters.

1. Double-click on !Boot and choose the Network icon. 2. From the Network configuration window, click on the Internet icon to display the Internet configuration dialogue box. 3. Enable the TCP/IP Protocol suite. 4. Click on the Host names icon. The Host names dialogue will be displayed: Hcstmmes Host name | BASl^TRTj

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Primary name senAf 158.152.1.43

Seoandary nameeerver 158.152.1.58 Te^eary none sarver | Name mswiuie j Basofwr fAoofn) ^ ^ USd hosts file oniy (B Use name serversalso

l>opa new Hosts File hereto raptace the ! ©)(j^n8 copy :• - 'k Hosts lile... J Cancat jj Srt J 5. Enter your node name (e.g.bashstreet., provided by your service provider) as the Host name. 6. Set the option Use name servers also. 7. Enter your service provider's domain name (e.g. demon.co.uk) as the Local domain. 8. If required by your service provider, enter at least one IP address for your service provider's name servers in the subsequent boxes, in the fonnat 158.152.1.58 (the first name server for Demon, for example). An alternative name server can speed up connection times if the first server is not * available for any reason. 9. Click on Set, Close the dialogue box and Save the network configuration. Ignore any warning box that complains about interfaces not having IP addresses configured, then reset your machine. 10. Your machine is now configured to use the Internet network stack. 3 Configuring the Internet server

Before you can start using Acom Internet software, you have to set a number of user options to suit your own requirements and those of your Internet Service Provider NB: Configuration requires some care, asdifferent Internet Service Providers (ISPs) require different settings. As a guide, we have provided example configurations in the form ofcompleted dialogue boxes for the three main types ofconnection. You can use these examples tohelp you complete theconfiguration dialogue boxes in this and subsequent chapters. Setting up communications functions

Double-click on IConnect (in the Network directory) toload it. Press Menu over its icon on the icon bar and the IConnect menu will be displayed:

tnfo ^ OonSgure > Adrrin Repojts Connect... ShoMTiog Finger ^ DIrecftiriee,.. Connect ^ Oscofnnect Msws... Quit Admin... Usethe Configure sub-menu to set up

1. the telephone line connection 2. the modem interface 3. the iPost_In and !Post_Out directories 4. the mail address anddiscspace 5. the newsaddress anddisc space 6.administration- local monitoring andcontrol of mail andnews services. Setting up the telephone connection When set up, Acom Intemet software will periodically dial up the service provider to send and receiveemail and news articles. IConnect allows you tocontrol your connection with the email and news service provider.

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In thisdialogue box, typein (orchoose) the Service Provider you are using (choose one or else enter their details) theLocationof theservice provider their Telephone number (prefix with a9ifrequired) BASHSTHTl their Gateway (service provider's Internet address). This option is only

W'i'*!.*?' *'*'*-:4 A Set Cheap ratetimes (from your telephone company). IfStart time isless than or equalto End time, the nextday is assumed. Setthe values which suityour usage

Set your Connection times:

Connect automatically when there are (fill in the number you want) mail messages or Newsarticles waiting to be sent Connect every (fill in the number you want) minutes at the cheap rate Connect every (fill in the number you want) minutes at the peak rate Disconnects the line when there isno browser activity for aset time. This savesyoumoneyif you forgetyou are cormected When ticked, connects with your Service Provider automatically when I you start IBrowse

•WySt;rhF4@!'>l:M If an attempt to connect fails (because the line is busy, for example), the Acorn Internet server will retry five times before giving up and waiting until the next scheduled time. Trial and error will be necessary for you to set the telephone connection detaUs to suit your own needs. It is aquestion of getting the best balance between call costs and response times. Clf-dy, It rs cheaper to use the telephone line at cheap rate times, but communication will be slow if you wart until the evenmg to send and receive mail -you won't get areply until the next day (or even later if addressees wait until their cheap rate too). There is also likely to be heavy Une usage at the start of the' cheap rate, which may delay connection. Similarly, if response tunes are important to you, you should set alow number of messages threshold, for more frequent connection, but athigher cost. Modem configuration The Configure/Modem option sets the computer to talk to the modem in away the modem expects -it does not configure the modem itself. ^nter new values or accept the defaults provided in the Modem Connection dialogue box: Set up your ModemConnectionas follows:

Choose the Model of modem you are using -either one listed, or acompatible Enter the characters which the modem requires to Initialise (start) it(see your iBii modem handbook +4^ATH Type in the characters which the modem requires to Hang up(stop) (see modem MVI^^i|l|J|||l]j,lSflfy handbook) Enter your modem operation Speed (see modem handbook). Set the fastest serial line speed your computer can support (see below) Choose the type ofdialling your phone system uses - Tone orold-fashioned Pulse dialling. Lift up your phone and press adial button -ifitplays a note you have Tone, otherwise Pulse

Compressioti techniques mean that the nominal modem -modem data rate can be greatly exceeded between the modem and the computer, provided that the modem and the computer can support such higher speeds. The following serial line speeds are suggested for use in the Modem dialogue box for different Acorn computer models:

A310, A440, A400/1 series, A3000, A3010, A3020, A4000: 9600 A5000:19200 Rise PC: 57,600 (14,400 baud modem) 115,200 (28,800 modem or above) When you have completed the dialogue box, click on Set to confirm your settings (or Cancel to leave settings unaltered). Setting up !Post_ln and !Post_Out directories

!Post_In is the directory on the server from which email messages and news articles received from the Internet are despatched to users.

•P08|_Out is similarly the directory towhich users send email messages and news articles for internal circulation and for despatch tothe Internet. This directory can be on the mail server machine orlocated on a remote computer.

Set up your Mail directories as follows:

Drag the !Post_In applicationicon to this box Dragthe!Post_Outapplication iconto thisbox : OK^ f Click on OK.

Entering your mail address and mail disc space The mail address is entered automatically for you ifyou choose a service provider from the menu icon on the Connection dialogue box (see Setting up the telephone connection). If you are using aservice provider not listed, you will be given amail address by the service provider, and this you must enter in the Hosts file whichyou can access by double-clicking on !Boot, then clicking on Network, followed by Internet, Host names and finally the Hosts file... button. The relevant line in that file will be similar to 158.152.1.72 post.demon.co.uk ^ ^

In this particular case, post is the mail address.

Now enter this address, together with other details, in the Configure/Mail... dialogue box:

Serverr

Address postderrx>n.co.L(k Type in or choose; FOPS Address

Oomain The mail Protocol (SMTP or POP3: see your service provider) Your mail Address (from your service provider) Your Domain name (usually node name + service provider's address, although Protocol tS'SMTP .JP0P3 some service providers do not use node names) Your POP3 user name (if applicable: see your service provider) P0P3 user The maximum Disc space you want to make available for mail The size limit for one message (to prevent accidental oversize mailings l>sc space limit j 20 {MB paralysing your machine) Kfaximum message size ^[loooj KB Set j Cancel j

You should setthe disc space to themaximum youcan spare to contain email messages to be received and waiting to be sent. When this limit is reached, no more incoming or outgoing mail will be accepted. Entering your news address and disc space

news address is similarly entered automatically for youif you choose a service provider listed in the Connection dialogue box(see Setting upthetelephone connection). If youare using onenot listed, you will be given a news address by the service provider, andthis you must enter in the Hosts file which youcan access by double-clicking on !Boot, then clicking on Network, followed by Internet, Host names and finally the Hosts file... button. The relevant line in that file will be similar to M \ i 158.152.254.254 news.demon.co.uk

In this particular case, news is the news address.

Now enter this address, together with your oiganisation name in the News... configuration dialogue box: I V News obnfigurafon N8vy$$drvi^ AdcNss news-demon.co.ul^ Type in:

^finisatton Bash Street School Your service provider's news Address Your Organisation name (if you have one, otherwise leave blank) CH^ space Hmif 20 The maximum Disc space available for News

You should set the disc spaceto the maximum you can spareto be taken up by news. Whenthe limit is reached, new news items will replace old, and a warning will be displayed in the server log. Configuring administration options

Clicking onConfigure/Admin...will display a dialogue boxfrom which youcanseta number of system management functions:

In the Administration dialogue box; Adn^r^tratormailrtame postmaster

adfi^nistratof Jf an sow occurs Type in the user name of the local network manager (Administrator). The user 'postmaster' has already been added. Mall aMr^trator ifserver warning occurs Tick if errors and warnings in the server log should be Mailed to fT" Copy censored maiJ to the network manager Copy bc^Ficedmaii to administrator Tick if mail to or from a censored address should be Copied to the network manager : ymftiogtiie to. ioo feies Tick if mail which cannot be delivered for some reason (e.g. Show detailed tog unknown address) should be Copied to the network manager Set the number of lines you want to keep Cancel 1 1 ^ Displaymoreinformation on the I(^

Notethat you must set up a usercalled ^postmaster' to receive Admin messages. Setting up users

Before you can use Acorn Internet software, you must enter the details of at least one user into the mail server: see Setting up users and user groups to find out how to do this. 4 Configuring !Mail

Installing IMall

!Mai!is the application by which you access email and news. Copy it to suitable directory. Setting the Postjn and Post_Out directories

Load !Mail (double-click on its icon in the Network directory).

Enter your Usename and Password in the Mail logon dialogue box).

Choose Configure... from the IMail icon bar menu:

Dragthe !Post_Iii application icon (from the Network directory) to the top box inSguratot Dragthe !Post_Oiit application icon . t II liu • ' . Postjn iocati

Changing your password

(Youwill not be able to use this option if Lock password has been set in the mail server.)

It is a good idea to change your password from time to time for security reasons.

To do this, choose Password... from the IMail icon bar menu:

Old password

New password

New password Cancol (

Type in your old password, then your new one twice, just in case you make an error.

That is all the setting-up !Mail requires. 5 Configuring the Web browser

You mustconfigure !WebServe (theWeb browser proxy/cache server) andthe browser itself, IBrowse.

Note: the Browser has been designed to work on a single machine, or over a network. So if you are a single user, you will see options which do not apply to your use. Page caches

Web pages usually contain colour images, hence tend to be large in file size. Someeven contain audio and full-motion video files as well, so they take a comparatively long time to load down the telephoneline or network.

Foe this reason it is very useful to be able to 'cache' (store) frequently-used pages nearer to the computer v'^e they are tobeviewed. Pages can becached on a stand-alone computer orona 'cache-server' for a local network ifyou have one.

Your Internet service provider may also offer a cache server at its point of presence, to cut out the time taken to load pages from the Internetitself.You may also wish to use a third-party cache, such as that at Demon (see below).

The proxy/cache server

The Acorn Internet proxy/cache server (!WebServe) allows your computer to cache pages locally and to look for them on a remote server. You should configure this before you start using the Web browser.

Configuring the remote server path

Wuble-click on the !WebServe icon (in IBoot.Resources) to load the application onto your icon bar.

Click Adjust on the WebServe icon bar icon to display the WebServe choices dialogue box (or choose Choices... from the icon bar menu):

WebS&fva choices &iter the following details for Webserve: Server fnformation

] Remotsproxy hUp:/'/Virww-Gache.dsmon oo.uh:8080 If your service supplier has a proxy server, enter its address and port number in the Remote proxy field. Your supplier will tell i CachsBizs W r 819^1 /-i you what this is. (This is not obligatory.) Mbx. oonnsct t2| &iter the Cache size required and the Maximum number of simultaneous connections you want to allow to the cache (10-12 Local port 80 *b1 is an average number: too many will slow down the response time). Connection ~ &iter the TCP/IP port number of the mail server machine used ' jAssume cofinedidn <6 akeady active ^ for connecting with its local clients. This is set by default to 80, which is the normal value.

will trt with twow iinlAea you tick Assume ctHiuection is already active. Tick the next option not to allow other machines to connect I Showan icon bar icon with the the server "f Finally, you can choosewhetheror not WebServe displaysan icon bar icon.

Clicking Select on the WebServe icon bar icon (or choosing Status... from the menu) will display the current status of proxy cache access. Setting the local cache size and expiry times

The Web browser will cache pages on a machine's hard disc in an application called IWebCache, which IWebServe expects to find in the same directory as itself.

Load IConnect, then choose Admin/Expiry timesAJRLs from the !Connect icon bar menu. The URL e^irytimes dialogue box will be displayed:

URL cac^ size j 1Q [ MB DefauR expiry time ie p?" /_\

Exf^rytime bar URL (S I defeiuii / jx days. Cancel \ Rush URL cache

Type in the amount of space on your hard disc you can devote to caching Web pages: a minimum of 10MB is recommended. A larger cache will perform better if you are using the Web heavily. When the space limit is reached, the least-recently-used site will be flushed from the cache.

S., the Default expiry time for cached Web pages. Cached pages will be flushed when they reach their expiry time.

You can specify a different expiry time for (an) individual page(s) if you enter its address in the 'Expiry time for URL' box and set its new expiry time. You will want to flush some pages, such as satellite weather pictures, after only a day or so.

Flushing the cache

If you need to flush (clear out) your page cache, for whatever reason, choose Flush cache from the WebServe icon bar menu.

Making the proxy/cache server available to other Web Browsers iWebServe will only serve pages to users IConnect knows about and who have Web access. If you are using other (possibly non-Acom) Web Browsers as well as Acom Internet software, however, it is possible for these browsers to be served pages by IWebServe as a usercalled ^alien' has beenregistered with !Connect and given Web access. Inthis way a request for a page from another Browser will not beblocked by !Connect. Browser configuration

Double-click on IBrowse to load it onto your icon bar. Changing the way the Web browser looks

You canchange theway theWeb browser looks by using the options on theChoices icon bar menu to show or hide certain graphical elements in the Web browser window.

There are seven Choices dialogue boxes: the first to be displayedis the Page dialogue box:

Horns Mtp://www.acc^n.co.uk^rowser/ j| 0 1 vj Browser Page (^ipiay IOCotoors Page Choices: UndeHme fenks 5^ Fonts Enter the URL (address) of your Home page fv Use documents colours Tick to show links uoderltned f/ Show foreground images I! ^ Tick to use the colours from the page Tick to display images Show background images ^ .^Others Tick to display backgrounds Document encoding Choose the character set used by the browser (leave at for European languages) ; Mcrosoft Latin-I (CP1252) Cancei \

You canprevent inline images and backgrounds from being loaded when you're viewing pages. Because the Webbrowser needs to load onlythe text for the page and not the graphics files associated with any inline images, selecting these options can make page loading much faster.

Changes you make here affect new browser windows only.

Click on Browser to display the Browser window dialogue box:

Browser Choices:

Tick to:

Display the URL field {7 Show URL bar Display the status bar ..[7-Showsu^s bar Display the button (option) bar [y StKW buRSsri bar Changesyou make hereaffectnew browserwindows only.

Page fettling j Notdisplaying thesegivesyou moreroomfor contenton the screen. ]7 Support extent iXiii t' •!- r-.r You can also: Support frames •• 1 SupportClient Pull (automatic reloading of web pages) fT" Pretend to be Navigator*^ Support Frames Pretendto be Navigator™ (somepages onlylet you in if thisis ticked,others may only work if it is unticked

Any changes you make here will apply to new page fetches. Click on Colours to display the Colours dialogue box:

B^Horound T}\ !Et Followed; ^ Choose: Foreground Highlighted The colour of the background The colour for text (foreground) |u new dabetlfe be dico fefifedo The colour for new unselected links lo followed fodedo di dibe befa The colour for links you have followed The highlight colour jada highlighted badi fefa cece .1.- T-^ -j:

Changes you make to Colours will take immediate effect on open windows. HTML pages which specify their own colours will override these choices (unless Display/Use document colours is off for that window).

Click on Fonts to display the Fonts dialogue box:

Basic display fonts - Body text Cmpus.Mecfium Font Choices: Headings Set the standard main Body text font Fixed {Homerton.Medium Set the standard Headings font Base size | 12.0 point Set the standard Fixed-width font (for code fragments, ReadMe files, and so on) Set the Base size for fonts used by the Browser PRE aspect j 100 /A % Set the aspect ratio (i.e. the relationship between the height and the width) ofthe fixed-width font used. Values less than 100% give a narrower, more iUse systemfont space-efficient font. PRE is one of the html tags using a fixed-width font. You can alternatively choose system font for use in the Browser.

Changes you make to Fonts will take immediate effect on open windows

Click on Hotlist to display the Hotlist dialogue box: Save 1WhenRanged Dj^>Ni.y: IPage iteecrip^one HotUst Choices:

Drag and

Any changes you make to the Hotlist will take effect immeciiately.

Click on History to display the History dialogue box:

Hi story • History list Choices: .' .:Save. iOn ouit } T Choose whether to and if so when to Save pages visted in the current session Osptay IPage itesaipBons Display the pagesvisitedby theirPage descriptions or by their URLs Keep a Historylist of Pages or Images visited ^ Page history Image history E)^ry Choose the Expiry criteria for your history list: Expire by age: itemswill be deletedfrom the list after the timeyou set here: Expire by age Set the numberof Minutes, Hours, Days,Weeksor Months after whichitems Expiry age [ 7 /JJi|Days will be deleted Expire by age: items willbe deleted from the list when their total size exceeds j: IExpire by size the value you set here: Set the number of KBytes for the History list file; when this size is reached old items will be deleted

Any changes you make to the History list will take effect immediately,

on Others to display the Others dialogue box:

You can choose whether or rmt your Browser supports Tables on the next and subsequent fetches. Tables . . - - . . If tables are allowed, then you can set the type of borders (if any) you want displayed (2D,3D or Auto2D/3D).Changing bordershasan immediate effect. I Support labios Choosewhetheror not to supportdata typesrequiringhelper' applications, or Cell bofdefs IT^to 20/3D * 'Plug-ins' (see Playing other multimediatypes). ij Outer table border jAuto20/3D ' If you do allow the Browser to support these data types,you can choose the point at which Plug-ins are launched:

17* SuppQft 01:^ ect. Applet and Embed Don't start ' :T^lug-'m [startwhenvievredon page Only when the data is viewed on the page, or As soon as possible.

[7^Usea}oca!pro)^{d.g. IWetsServe} ' Hug-ins require quite a lot of memory to run, so you may not want them to load right away, or at all. Suppon for these objects will be active from the next fetch You can also choose whether or not you want to use a local proxy server, such as IWebServe. If you make a change to this option, click on Save; the change will take effect next time you start the Browser.

Network configuration

Sony, but this is unavailable from the front-end in this version. If you're feeling adventurous, you can always edit the !Browse.Choices file, but always take a backup copy to revert to if things go wrong. 6 Managing the mail server Setting up users and user groups

You enter all user names (evenyour name if you are a single user). Todo this, double-click on the !Connect icon in the Internetdirectory, to load !Connect. From iConnect's iconbar icon, choosethe Menu option Admin/Users.... This will display the Users dialogue box:

SagBafcteAIInWftitfi cdmsmfth

^4 u

'i ^ ^ A. -v ^ t Add

, ••-... '...A.?-.*

Enter each 'Usemame* in the User field. Usemames can be up to 19 characters long, passwords 10 characters. They should use only alpha and numericcharacters. They are not case-sensitive (i.e., t worksthe same as T). For maximum securitypasswords should not be words found in the dictionary, and should include numbers as well as letters.

If you are use P0P3 mail delivery,you must create a user with the same name as your P0P3 Usemame, as it is to this user that mail will be addressed.

Users can change their passwords from the !Mail icon bar menu unless Lock password... is set. Youmay want to set this for shared accounts, where you don't want one user changing the password unilaterally.

System user option is for future expansion.

Network users can save time entering a large number of users by first listing their names in a plain text or CSV (Comma Separated Value) file, then saving the text file into the Usersdialogue box.You may already have such a list of users on your school administration system. Even DOS programs can often provide plain ASCn CSV data files, and your Acorn computer can read DOS floppy discs.

The format ofthe text file to add users can be any one ofthe following (to remove users, prefix the line with a minus instead of a plus):

+emailname password group Yes/No (Web) Yes/No (lockpassword) Yes/No (systemuser) fullname

+emailname,password,group,Yes/No,Yes/No,Yes/No,fullname

+"emailname","password","group","Yes/No","Yes/No","Yes/No","fullname" For example:

Enter users to be included in the group 'all*:

+rjohnson xroads all yes no no Robert Johnson

+cberry jonnybgOOd all yes no no Charles Berry etc

+jpage;5tairway,all,yes,no^no,James Page etc

Remove a user from the group 'Usixth':

-"efitzgerald","manhattan","USixth","yes","no","no","Ella Fitzgerald" Oer groups

In network use it is important to set up user groups, as it is by this mechanism that you can control access to particularnewsgroups and email to and from specific locations. For single-user application, however, it is not necessary to set these up. Managing newsgroups

Whenever IConnect connects with the service provider, articles from all newsgroups allowed are downloaded. If many newsgroups are allowed, this can involve a massiveamountof data. It is therefore important to ensure that you only allow newsgroups in which you have a specific interest, and keep their numbers to a minimum. Otherwise, downloading could take many hours!

S^.ilarly, just the titles of all the newsgroups available make up a largefile, so only the most commonly-used are included on the Acorn Internet software disc. These are listed in the file IConnect.Newsgroups. A very large Newsgroups file will consume a significant amount of RAM on your machine, so you may wish to remove unwanted lines inside the file (load it into Edit to do so).

Ifyou do want the complete up-to-date list, choose Update newsgroup list when next connected (see Allowing and disallowing newsgroups), but you do not have to leave this option switched on, as it will run up your connection charges unnecessarily.

Allowing and disallowing newsgroups

To allow or disallow a newsgroup, choose Admin/Newsgroups.... The following dialogue box will be displayed:

Choose the group (single-users leave at All) Type in or clioose via tlie list below the ^ newsgroup to be allowed or disallowed. You . I can use wildcards (see below) ^j8V4S5r^up Choose to download the complete list of newsgroups when connected (lengthy) jupctete newsgroup list when next connected Click on Allow, Disallow or Remove. Use the Adjust mouse button when dealing with Cancel Remove QSaOOW more than one newsgroup. Remove will I remove all access toa newsgroup. Disaliow a.bsui* (3 groups) jI will disallow access to that user group only. ab.* (4 groups) abg,* (6 groups) I i Inthe list ofnewsgroups below, sub-groups will cascade abulafia.general O when parent groups are chosen, making selection Hh quicker

(The newsgroups themselves will only be loaded once you have connected to your service provider.)

The menu which lists available newsgroups has a writable line at the top where you can enter the name of the newsgroup in which you are interested, or you can click on the newsgroup listed. lUke server does not find the file "Newsgroups' inside the '!Connect' application, it will load a full list from the service provider.

Using wildcards You can speed up the process of allowing and disallowing newsgroups by using wildcards when you specify newsgroups. This is useful because there are so many of them. Wildcards are (usually) single characters which stand in for several characters of a similar type. Two wildcards are available for describing newsgroups:

* meaning any number and type of letter <3tring> where string is any sequence of characters.

So, comp. * would mean all the newsgroups which start comp. , such as comp. sys. acorn for example. o^ltur>would signify all newsgroups with cultur anywhere in their title (such as culture and cultural).

would cover all newsgroups with politic anywhere in their title (such as politics, politicians and political).

could be used to disallow all newsgroups with sex anywhere in their title (including, for example, Essex).

Newsgroup expiry times You can configure how long news articles remain accessible.

Obviously, very old articles lose their topicality and need to be deleted to make room for new ones. The default life for a news article is seven days, but this may be changed using Admin/Expiry times/Newsgroups. Newsgroups with a high volume of traffic might be set to keep their articles a shorter time than those with a low volume, for example, to avoid the hard disc filling up too quickly.

URL cache 8a» 110 | MB DefauH exptry ttmB is ^7 / days Set the default ecpiry time for the system For specific oewsgroups, set individual expiry times. Youcan Expirytime for URL use wildcards Confirm or cancel your choice

Cancef Flush URL cache

Allowing and disallowing Web URLs You can allow or disallow a Web URL to a particular group of users in much the same way you censor v'sgroups. Choose Admin/URLs... and the following dialogue box will be displayed:

Choose the group Group' AB Type in or choose via the menu icon the URL to be allowed or disallowed. You can use wildcards (see above) Click on Allow or Disallow. Use the Adjust button when dealing with more than one URL Cancel U . Altow j Disaiiow

Mail statistics

A number of mail reports are available to the network manager to help judge the performance of the system, how much it is being used, and by whom. These reports are available from the menu option P^iorts/Statistics, andarelargely self-explanatory:

Allowed groups (allowed newsgroups, by user, group and total). Subscribed groups in the case of the single-user version ofAcorn Internet software. Connect times (a list of recent connection times) Disc usage (by user, group and total) Censorship (a list of disallowed addresses by user group).

Each of these subjects leads to a Save dialogue box - drag the textfile icon to !Edit to view the report, or to a printer to print it out. Displaying the server log

You candisplay theAcorn Internet software server communications logby choosing Show log from the Connect main menu: V-'fWr;. 28/02 12i33!3fli RRTICLE 42474 28/02 i2i33!39! Script .fr»vi4»rs.fl»rii.8«ript ;tirt«il 28/12 i2i38;30i II931I: WMKi Ui« is 12:43 28/12 12:33:331 Script canplctpd

The server log tracks the activities of the server as they occur. This is useful for netwoik management and tracing problems. Saving the server log

When you quit Connect, the current log is saved to disc as the file Log inside !Connect. Log file messages

Do not be alarmed if some of the text in the log appears truncated- "Got rotocol" for example. This is often Ir^use service providers use a mixture of upper and lower case letters, the first letter being ignored when matching text strings.

RMEnsure messages are displayed complete, together with their associated error messages, but this does not necessarily mean than an error has occurred. Finger

Finger, available from the Connect main menu, is a convenient way of interrogating a service provider.

Faiaer

[email protected] f Finger (

Typing in:

@post.demon.co.uk for example, would return details of any mail waiting forat the service provider demon. Quitting Connect

Exit from Connect by choosing Quit from the IConnect icon bar menu. Saving space

Alist ofthe more commonly-accessed newsgroups is supplied. It is held in the file IConnect.Newsgroups.If you want a complete list, simply delete this file, and !Connect willload another from the service provider next time you connect. However, this list is large, (approximately 200K) and you can save space if you subsequently delete entries in which you are unlikely to have any interest. Deletion can beperformed by dragging the file to !Edit, manually deleting unwanted sections, andthen saving thefile again. 7 Using !Mail

First ensure that both the Internet server,!Connect and the client application IMail have been installed and correctly configured (see Setting up. Configuring the Internet server and Configuring IMail). Starting iConnect

Check that the modem is connected both to the telephone wall socket and to the serial port of the server, then switch it on. Open the Network directory and double-click on IConnect. Double-click on IWebServe.

(If you do not intend to use the Web browser, you do not need to load IWebServe as well.)

/Amatively, youcan start the mail server automatically byincluding lines similar to thefollowing in your boot file:

Filer_Boot adfs::4.$.Network.iSerialDev

Filer_Run adfs::4.$.Network.!Internet

Filer_Run adfs::4.$.Network.!Connect

Filer_Boot adfs::4Network.IWebCache

Filer_Run adfs::4Network.IWebServe

(This assumes the applications are stored in a directory entitled Network in the root of your hard disc.) connecting with the maii system

Double-click on the IMail icon and the logon dialogue box will appear on your screen (except when you are a single user): ♦

Type in your user name (your network manager will tell you what this is) lype in your password (your network manager will tell you what this is) Click on Logon to log on, Cancel to quit

The Mail icon BBHwill appear on your icon bar, grey atfirst, then red with your user name undemeathonce your logon has been authenticated: When there is mail waiting for you, it will appear like this:

If Post_In and Post_Out have not been set (see Setting up !Post_In and !Post_Out directories), or ifthe network is down, or mail server machine not switched on, the postbox icon will appear with a question mark.

You can now connect with the Internet. Sending mall

To send mail, you must first write the text of your mail message in Edit or other plain text editor. Don't worry about addresses - just start at "Hi Bob," (or whatever) and end at "Regards, Chuck". Save this Edit file onto the Mail icon (on the icon bar). The mail window will be displayed:

Send mail From fctoerry "(Chartes Berry) (From) your name (entered automatically) rjohnson

• ^ (To) type in the destination name and address (if more than one name, separate by a comma). Youcan use distribution lists, too Invitao'ofj ^Acknowledge Anyone to be copied (cc) Fill in the subject (about) " ' Click ifyou want an acknowledgement ofreceipt ^ Qob!

Your message What SfS you doing at the weekend?

Click tosend got a fewTidewaterfriertds at my house on Saturday

Drop any attachments you want to send in the blank area at the bottom of ' the window .

The text of your message will be displayed in the message area, and your name will be filled in automatically.

All you have to do is to fill in the name and address of the person you are sending the message to, (optionally) anyone to be sent a copy (CC - stands for carbon copy, using an old analogy!) and the About field. Take care with the name and address of the recipient - they are often long and obscure and easy to get wrong: if you make a mistake, however small, the mail will not get through.

For local email (to other users on the same site), their user name alone is enough to send them a message. The user group name is not required.

Drag any attachments you also want to send, such as other text files or pictures, for example, to the bar at the bottom of the window; these will accompany your message when it is sent, as long as the destination machine understands RISC OS and the standard MIME email format. IfAcorn Internet software is running at both ends, attachments will arrive as posted.

If you want to change the message, or any of the attachments, at this stage, click on the Cancel icon, and start again.

"When you are happy with your message, click on Send, and the message will be sent next time you are connected with your service provider (see Connecting with the Internet).

Acknowledgements

You can make reasonably sure that the message you send has been delivered and/or read by its addressee, by choosing Acknowledge. For remote mail a check is made that it has been written to the recipient's mail server; local machines check that the message has been opened on the addressee's computer. B^ading mail

Incoming mail is held in a mail box at your service provider, and is downloaded when you connect.

Checking If you have mall to download

Any mail held for you by your service provider will be downloaded automatically as soon as you connect (see Connecting with the Internet); however, it is sometimes useful to check directly ifthere is any mail for

When you have connected with your service provider, choose Finger from the IConnect icon bar menu. Check that your node name is entered correctly in the dialogue box and click on the button. Whether or not your service provider has any mail for you will be indicated on the Server log.

PBadlng your mall

When your mail icon looks like this: you have a mail message waiting on your local server. To read it, click on the mail icon; your current mail folder will appear

The top message is unread r^"-Charffis

You have read the lower one

To read a mall message To read a mail message, double-click on it, and it will be displayed in a message window.

Any attachments enclosed can be run by double-clicking onthem, orthey canbedragged and saved in another location.

Replying to a mall message

To reply to a message which you have just read (see above), click on Two things will happen:

The message just readwillappear in an Edit (or yourcurrent text-editor) window, eachline indented andprefixed by > characters, so that you can edit it andrefer to it if you want to, appending your comments in reply. A Send mail window will also be opened

i-at s- From [^ohn^n Johnson) IcberTy^comtstctemon.oo.uK (Charfes Berry)

In io^sfeartor message you wrote:

> >HQob\

>WhatafeyQu dc^atthe wee > Misc ^ SsMfliaa >IVe got 3 ^ Ttdewater fhencfe >m8et you, so could you come t Select ^ > ELetmdknowtfyoucanccHn6. Display ^

gg \ _Add your reply to the original message (edit if

2. Save your reply into the Send mall window

Edit the read message as you want to (or delete it altogether) and insert your reply text.

Save the reply into the Send mail window. The reply destination is already filled in, but you can change it and add or delete CC addressees if you want to.

You can add any attachments to be sent by dragging them to the bottom of the window (see Sending mail). They can be deleted using the Menu option available over the Send mail window.

Click on Send, naturally enough, to despatch the email. Forwarding a mail message Forwarding a mail message works very much like replying to one.

Click on lin the Mail window when you have read a message.

The message is repeated in an Edit window, in case you want to add anything to it. To forward the message, you save it into the Send mail window, but this time you have to add the name of the addressee as well. Deleting a mall message

Delete When you have read a mail message, and do not wish to keep it, press land the message will be removed. Saving a mail message

When you have read a mail message, and wish to save it, press ^ - land a Save dialogue box will be d- played, allowing you to save the mail message to a directory, printer or another application. Connecting with the Internet

Connect retains outgoing mail until you connect with your service provider.

Similarly, mail and news held for you by your service provider cannot be downloaded to Connect until you make this connection, nor can you browse the Web.

When you are ready to connect, choose Choose Connect/Mail only or /Mail and news to connect via the modem to your service provider. Any mail to be sent will then be despatched over the Internet, and mail addressed to you will be downloaded by your service provider. You can then use the Web browser, too.

^i^en you have finished with your connection, choose Disconnect from the Connect main menu. Logging off and Quitting

When you have finished using IMail, you can log off from the mail system by choosing Bye from the !Mail icon bar menu.

This will produce a log-in dialogue box for the next user.

To exit IMail altogether, choose Quit. 8 Using the Web browser Starting the Web browser

You can start the browser in one of two ways:

from IMail by itself. starting the browser from !Mall

To Start the browser from IMail, first ensure IConnect, IWebServe and IMail are running (see Starting !Connect and Connecting with the mail system) then press menu over the IMail icon bar icon and choose WWW...

1 - Web browser icon will appear on your icon bar.

Click on the browser icon bar icon and the Web browser window home page will be displayed on your screen:

(The window itself will not show any content if you are not connected to your service provider or a local cache.)

To use the browser over the Internet, IConnect must be connected by a telephone line to your service provider - see Connecting with the Internet. starting the browser by Itself

First load IConnect and IWebServe (see Starting IConnect). Display the directory containing !Browse and double-click on its icon. The Web browser icon will appear on your icon bar.

Click on the browser icon bar icon and log in with your usual name and password.

When your log-on has been authenticated, the Acorn Internet browser window will be displayed on your screen:

To use the browser over the Internet, IConnect must be connected by a telephone line to your service provider - see Connecting with the Internet.

We are now going to describe the way the browser works, as background to using it. Ifyou are anxious to start opening Web pages now, go straight to Opening a page directly.

Overview

Note: IBrowse is a "Frames capable' browser. 'Frames' in HTML divide the content area of the browser into separate windows, so that separate pages may be displayed in different windows at the same time. When you are given the opportunity to choose Web pages with or without Frames, you can therefore choose Frames ifyou want to.

The Web browser window is your window onto the World Wide Web. The diagram below shows its main features.

p./-nvvir i V IrM

Title bar(yellow strip)

Location field (URL)

Button bar (row of buttons)

Content area (where the page is displayed)

Status line at the bottom

Status indicator (Acorn)

Load indicator at the bottom righthand comer

Title bar

The title bar of the Web browser window shows the title of the current page - a brief description of what you're looking at. Not all pages have titles, and so sometimes you will see the page's URL shown in the title bar instead of a title.

Location field

Belowthe title bar, nearthe top ofthe Web browser window you'llseethe Location field. This shows you the URLof the currentpage and can also be used to enter the location (the URLaddress) of a page you wish to view next.

Toenterthe address of a page, carefully typein the URLandthen press the Return key on your keyboard.

See Identifying resources - URLs for more information on URLs and how they are constructed.

Button bar

URL http://www.acorn.com/acom/cofnpmiy^

The button bar contains eleven buttons: Home, Back, Reload, Stop, Forward, Hotlist,Add to HotUst, Save page source, Display page source, Print, Show images.

Home

Displays your designated Home Page.

Back

Returns to the previous page in the history list; for example, if you followed a hyperlink or selected a menu i>^, you can go back to the page you just came from. This is the same as the Navigate/Back one page menuitem. Obviously, if this is the first page you have displayed, there is no page to go back to, so the option is greyed out (as here).

Reload

Reloads the current page, displaying any changes made and saved since the page was last loaded. This is useful for checking an HTML file as you are creating it. stop

Stops the page transfer currently in progress.

Forward Brings the nextpagein the history list. (Available onlyafterusing the Back command or a History menu item.)

Hotlist

Displays the list of pages currently on your hotlist in the Hotlist window.

The hotlist is a way of getting easy and direct access to your favourite pages, without having to type in the URL of the page you want to visit, which is tedious and error-prone.It is a list of pages you have marked as interesting or notable. Once you add a page to your hotlist, the title stays until you remove it.

Click on the Hotlist button to open the Hotlist window, which lists the pages currently on your hotlist. Double-click on

Add to Hotlist

Add the currently-displayed page to your hotlist.

Save page source

Clicking on this button saves the current page source (i.e. in HTML). If the page displayed includesFrames, the file saved will be the parent file. To save a particular frame, place the cursor in the frame and use the menuoptionFile/Saveframe.

Display page source

Displays the current page in its source form (i.e. HTML). If the page displayed includes Frames, the file displayed will be the par^t file. hdnx

Prints the current page ifa printer is connected and set up. Show images

Switchesimages back on (if they have been switchedoff using the menu optionDisplay/Show foreground images or Show background Images.

Content area

Below the toolbar is the Content area, which displays the current page. Use the vertical and horizontalscroll bars to view pages larger than the content area.

Youcan view HTML-formatted text in the Content area, as well as images. If you click on a hyperlink to another type of file, for example, a sound file, an external helperapplication (if a suitable oneis available) will be started up to allow you to access the file. Status indicator, status iine and load progress

Status indicator

In the lower lefthand comer ofthe Web browser window is the Web browser status indicator (the modified Acom logo).

When you click on a hyperlink, the indicator animates, showing that a page is being retrieved.

Status line

The Status line at the bottom of the Web browser window displays the URL ofa linked page. When you ipsye thecursor around intheContent areaovera hyperlink, the URL of thelinkdestination is displayed in the Status line.

The Status line also displays information about the status ofthe current page retrieval. Examples ofstatus messages are:

Transfer in progress...

Ready

Load progress

Load progress is indicated by the number ofbytes ofdata loaded so far. Rnding, starting and stopping links

Links

A link is a connection from one page on the Web to another, or to another part of the same page. Links appear in a page as words or phrases that are highlighted with colour, underlining, or both. Images and icons with coloured borders also serve as links. A whole image may be a link, but some images are 'image maps', with more than one link over them. When you move the pointer over an image map, it turns into a cross-hairs to enable you to point at the part ofthe image map you want to click on more easily.

When you point the mouse cursor over a link, the URL of the link destination appears in the Status line at the bottom ofthe Web browser window. Starting links Todisplay a linked page onyour computer screen, youjustclick once onthe highlighted text, image, or icon. Clicking ona linktransfers thepage attheother end ofthelinkfrom theserver where it is stored to your computer.

After you click ona link, theWeb browser status indicator (the revolving Acorn) starts to animate to show you that the transfer of the page to your computer is in progress. stopping links

You canstop a transfer in progress by pressing theStop button onthetoolbar or by choosing the Navigate/Stop menu item.

You'll find that being ableto stop a transfer in progress is useful if it is taking a long time. This can happen if the contentof the page is large, for example, if it contains a largegraphic, or if the servercomputer is slow.

Sometimes the pagespecified by a linkis just notavailable. You'll usually get a message if a connection wasnot made or a pagenotfound. You can seehowa transfer is progressing from the Status line and how much of the page has been transferred so far from the Load projgress counter.

Navigating within a page

Whenyou follow a link, you'llsee the wholepage or, if the page contains morethan a screenful of information, part of it. Usethe scrollbarsto lookat the rest.The portion you see maybe the top of the page,but sometimes following a link may bringyou into a page at the middleor end. Following a linkdoes not alwaysbring a new page to screen- it can bring a differentportionof the samepage (in effect, automatically scrolling for you).

For example, the top of a page often includes a table of contents that links each section title to a section s^*)heading further down the page. Moving around

You move through the web ofinformation available online by following links.

You click on highlighted words (coloured and/or underlined) in a page to bring another page of related information to your screen. You click on titles in the Hotlist window to go directly to pages that you've already viewed, orwhich interest you. You click on buttoiis on the toolbar to go back and forth between pages you have previously visited.

The Webj^jvser buttonsand windows are designed to helpyou movequickly from page to page and also keep pages that you've viewed. Opening a page directly

The URLof the page you're looking at is displayedin the Locationfield at the top of the Web browser window.

Usually, youdon't needto knowa page'sURLbecause the location information is built into a highlighted link; all you need to do is click on highlightedtext, press a button, or select a menu item. But sometimes you won't have an automatic link and insteadhave only the text of the URL (perhaps from a friend or afrom a newspaper article).

The Web browser lets you type a URL directly either into the Location field or into the URL dialogue box which appears when you choose the Navigate/Open URL menu item. The Webbrowser uses the URLto bring you the specified page just as ifyou had clicked on an automatic link.

(^en theURL dialogue boxand trytyping in some ofthefollowing URLs: http://www.acorn.com/ http;//www.nhm.ac.uk/ http://www.rsnz.govt.nz/

To display a new page in a separate Web browser window, press the Menu mouse button over the Web browser icon on the icon bar at the bottom ofthe screen and choose Open URL from the menu. Then type the URLfor the page into the URL dialogue box.

The browser menu

options available from the button bar, plus a lot more, are available from the browser menu. Press the ^wllu button over the browser window in order to display the menu. The following main menu options are shown:

File Display Navigate Hotlist History.

File menu options

Using the browser menu, you can Save

the frame the pointer is over the parent of the frame the pointer is over The currentlocation (URL) as a file. Clicking on the file opensthe browserwindow and tries toload the location.

You can also Export the current page or fi*ame as

a Drawfile plain text and also Export

the page as a Link the Pictures on the page the Background ofthe page

You can also Print the current page from the File menu, as from the button bar. Plsplay menu options

The control and information bars are very useful, but they do take up some of the browser window area otherwise used for content, so they can be deleted ifyou want. Tick the following options to display them:

URL bar Button bar Status bar

Note that button bar functions (and a lot more besides) are all available firom the browser Menu.

You can display links in text Underlined, or just in a different colour.

Not displaying images saves a lot of loadingtime. If this is importantto you, don't tick Show foreground images (i.e. pictures) and Show background images.

You can also display the browser Full screen: you gain more room for content, but temporarily lose some ofRISC OS's multi-tasking ability.

Document encoding governs the character set used by the browser. The Latin-1 set is normally used by European languages (including English), but other world language character sets are also available. Navigate menu options

The Navigate menu options generally repeat the options available from the button bar:

Open URL Home page Back one page Forward one page Reload this page Load all Images (if switched offusing the options Display/(do not)Show imagesmentioned above). Stop all fetches.

Hotlist menu options

The Show hotlist.. and Add this page (to hotlist)options allow you to use the hotlistwithout the button bar. History menu options

Using the Utilities menuoption,you can Find text... in the currently-displayed page, whichcan be very useful when some Web pages continue for many conventional pages.

final menu option allows you to Quit the browser. The browsericon disappears from the icon bar. Viewing iocaliy-stored pages

As well as fetching and displaying pages from the far comers of the Internet,the Webbrowser also lets you look at pages stored locally on your own local network.

Choose the Navigate/Open URL... menu item to display the Open URL dialogue box. Youcan then specify the page you want to view in one oftwo ways: Enter the filename ofthe HTMLfile and then click on Open. Choose a page from the drop-down History list

Alternatively, you can selectthe HTMLfile icon and drag it onto the Webbrowserwindowor onto the Web browser icon on the desktop icon bar. 9 Using news

A newsgroup is a silent forum where all sorts of things are discussed - opinions aired, advice sought, souls bared and, at times, spleens vented. It is like a global bulletin board where ^subscribers' to a newsgroup ^post' articles which can then be seen by subscribers all around the world. Reading news

(!Mail must first be loaded and IConnect running.) Displaying your list of newsgroups

When you want to read news, choose the News... option from the Mail icon bar menu, or click Adjust on t^Mail icon.A list of the newsgroups currently allowed (see Managing newsgroups) is displayed:

Articles unread on left

000 000 soc.cufture.bottvia Articles readonright 000 OOD rec.Wt^ 000 000 oomp-sys.acorn

Displaying the list of threads

A thread is a line of discussion running in a newsgroup - someone posts an opinion, perhaps, then a number of subscribers comment on it. The original poster then responds, and so on. Threads can be as short as one afticle, or may go on for days or even weeks.

Double-click on the newsgroup you want to look at, and a list of current threads in that group is displayed:

1^

000 001 DeskUb - info please. oot 000 Help required on oornp.sys acorn.^ 00? 000 Run$path oot OGO Movinga window wj^ou! the t^ bar 001 000 A bit iate to of this (dynamic SWf chunks) 001 000 Termite Internet

Hiding read articles

If you haveread many of the threads, you may wish to save time and screen spaceby displaying only those you have notread - press Menu over thethreads window and choose Unread only; I Displaying the list of articles

Double-click on a thread to display the articles window, which contains the current list of readand unread articles in that thread:

EZU Mon, 06Oct 199714:56:06 tOia I 17^ James Larcofhbe I | ZlJ 06Octl997;21;O6:4$+OT00 U "A.R Taylor m SSi Mon, 06Oct199719:48.-09 *010

Displaying an article

F^ble-clicking on a particular article will display it in a window similar to the mail window:

From 1aoorTitst<§>awfh^.demon.oo uk

About [AfflKnlnterratSoftware Next I i Forward | FoUowup j fle

Click on N«t to read the next article in the thread (if there is Acorn Internet software gives you everything you need to browse the World Hide Web« send and receive eoiail, and read and participate one) in global newsgroups.

Click on Previous to read the Acorn internet software is easy to install, configure and to use. previous article (if there is Great enphasis has been placed on control and observation, to ensurt one) that users have access only to approved newsgroups, email addresses and Web pages. It also helps you control telephone line costs, with frequency and length of connection being fully configurable. Reports on connect tines, news and enail voiiine are available to the user at any tine.

Forwarding an article by email

F'Orwsi'cf I Click on the Ibutton in the article window.

Two windows will be displayed:

An Edit window, containing the text of the original article A Send mail window.

Edit the text of the article if you want to, then save it into the Send mail window.

Enterthe name and address of the person you areforwarding the article to, and click on Send.

From I aoomtstJslacQfn^.demon.oo.uk

yjuisiu

Acorn Inter the Worid w Be: Acom in global n i-ia'tre f 2 In an article on dewon^test, acorntste ^ >flcorn Internet software gives you eve >the Norld Hide Hebj send and receive ^ ^ >in global newsgroups. Display >Rcorn Internet software is easy to install configui >6feat ef^hasis has been placed on control and obser' >that users have access only to approved newsgroups, >and Heb pages. It also helps you control telephone >line costs, with frequency and length of connection Configurable. Reports on connect tifies, news and en >are available to the user at any tine.

Following up an article

I^^u want to join in a thread (your contribution will be posted for all subscribersto read), click on 1—j-OHOWUp!^—,Jliand an—cj:* Editwindow willopen. The article to which you are responding will be included,iT>M,^AaA indented and marked with a >, ready for you to edit it if you wish and to add your own posting.

OHowup Reply

Acorn Internet software gives you everything you need to browse and read and partlclpat n an earlier article acorntsteacorntst. >ficorn Internet software gives you everyt >the Horld Hide Heb, send and receive ena h tto use. >in global newsgroups. wmmmmJ to ensur >Rcorn Internet software is easy to insta Seled >Great enphasis has been placed on contro Edit fuiiy Hhat users have access only to approved >and Heb pages. It also helps you controii "^spiayDisplay TexiFil >line costs, with frequency and length of connection >configurable. Reports on connect tines, news and en >are available to the user at any tine.

Save your posting back into its original window. ThePost article window willdisplay yourposting, and give you the chance to change the newsgroup name and subject lineif youwish, before youpress Post to despatch your new article:

d0mon.test

Abhut Re; Acom imemet Software

• Cancel. Acorn Internet eoftwa In an earlier article acorntstsecornt.st.de»on >Acorn Internet software gives you everything n an earner article ac >the World Wide Web, send and receive email, flcorn Internet software >the Horld Hide Heb, sen >in global newsgroups. >in global newsgroups. > > >Acorn Internet software is easy to ifistali, >flcorn Internet software >Great emphasis has been placed on control an >6reat eiw^hasis has been >that users have access only to approved news >that users have access >and Web pages. It also helps you control tel >and Hob pages. It also >linQ costs, with frequency and lei>gth of con >Hne costs, with freque Configurable. Reports o >are available to the us

Replying to an article (by email)

Sometimes you may wish to reply to the poster of an article by email, rather than by posting to the whole group.

To do this, press !ii—!. As with Follow up, the original posting is displayed inan Edit window, for you to edit and add your own contribution.

Save this Edit file into the Send mail window displayed. Alter the addressee, CC and subject lines if you wish, the press Send to send the email. Saving an article When you have read an article, if youwant to save a copy, press a Save dialogue boxwill be displayed, allowing you to save the articleto a directory, printeror anotherapplication. Starting a new thread

If youwish to respond to an article youhaveread, usethe procedure described in Following up an article.

Otherwise, to start a new thread

1. write your article in Edit 2. save it into the threads window - the Post article window will be displayed 3. fill in the subject field 4. click on Post to send the posting off.

Your article wiU be posted to the newsgroup. 10 Playing other multimedia data types

Sometimes you willcome across Web pages which contain multimedia datatypes andexecutable code which your browser may recpgnise butdoes nothave the ability to runor display itself. Toplay them you need to have a 'helper' program (a 'run-time environment' or'player') onyourcomputer to handle the particular data. These usually display thedata inside your browser window, sothat it appears that the browser is in fact handling the data.

Examples of thesealien datatypes are: Shockwave movies (created by MacroMedia Director), Javaapplets (browserprograms createdusingthe Java language) and high-quality digital sound.

The latestversion of AcornInternet softwarehas been designedto accept 'plug-in'playersto handle a numberof differenttypes of data you may encounteron Web pages: Java and Shockwave players are currently available for Acorn computers.

If your computerhasthe right player, and it has been 'seen' by the Filer,you can usuallydownloadone of these data types from the Web and play them on your computer automatically, without having to worry about how the player woiks.

Ifthe multimedia file includes sound, you will need 16-bit digital audio hardware in your computer in order to be able to listen to it.

We cover two multimedia players in this chapter:!Java for playing Java applets and IPlayer, which plays Shockwave movies. Playing Java applets

Java applets downloaded from the World Wide Web can be played on a RISC OS computerby !Java.! Java RISC OS plug-in player, or run-time environment, which is called upon by the browser when it is required to play Java applets.

!Java is supplied with the latest version ofAcorn Internet software, and should be installed on your hard disc as suggestedin the Release Note suppliedwith the software.Please take note ofthe minimum machine RAM requirements required to run!Java on your computer, also detailed in the Release Note.

What is Java?

Java is a programming language, similar in appearance to C++ but a completely new language in its own right, which has been develt^ed for writing applications distributed over a netwOTk. Networkdistribution poses severe challenges for software developers because of the wide range ofclient computer platforms connected to the Internet: wcffkstations with SPARC, Motorola, DEC Alpha or Intel processors. Acorns with ARM processors, PCs witii Intel or PowerPC processes. Macintoshes with Motorola or PowerPC processors. For each one ofthese would a program have tobe separately compiled to make sure that it would run once it had been downloaded.

Platform independent

Java is 'platform independent'; that is to say that the same applet willrun on any computer with a Java player connected to theInternet. How is this possible? Well, every Java applet is part-compiled into bytecode for a single target computer, the 'Java Virtual Machine'. This target computer, as its name implies, does notexist in reality; it isjust a standard to which all Java code must adhere. Java is aninterpreted language, soeach computer ontheInternet which wants to runa Java applet must have a standard Java interpreter (standard asfarasitsinterface with the applet is concerned). The interpreter will always run the Javacodein the sameway, irrespective of the machine on which it resides. In this wayonlythe Java interpreter hasto be ported onceto eachtypeof computer, notevery applet you want to run on it.

Secure

Downloading data from the Internet is relatively secure - dataalonecannot introduce viruses into your computer. Executable codeis another matter: youwill naturally be concerned about downloading programs from a sourceaboutwhichyou mayknow little.The authors of Java haveaddressed this concern by making Java code protect the integrity of your computer in the following ways:

1.The Java interpreterincludes a bytecodeverifier which checksthe code for languagecompliance before it is run on your computer. 2. It then determines the memory layout for the Java program 3. The interpretermakes sure that a Java programwill not accessthe computerfile systemexcept inthe specific maimer permitted by the client. Running Java applets

operation of!Java is transparent to the user. When you click on a Java applet on a Webpage, as long as it can find it (see the Release Note on where to install plug-ins), the Acorn Internet software plug-in interface will call!Java to handlethe applet, opening a window in your browser. Depending on the applet you have loaded, additional controls for the applet may also appear.

The presence of!Java is indicated by its icon appearing oa your icon bar.

Quitting IJava

!Java quits automatically a short time after you quit the last Java applet. The delay may be altered by editing the !Boot file. When!Java quits, it gives back all the memory it was using.

You can quit IJava manually by choosing Quit from the IJava icon bar menu. iShockwave !Shockwave is theplug-in RISC OS application which is summoned automatically byAcom Intemet software when it is required to play Shockwave movies. Atpresent!Shockwave will only play movies developed using Macromedia Director 4.

!Shockwave is supplied with thelatest version ofAcom Intemet software, and should be installed onyour hard disc as suggested in theRelease Note supplied with thesoftware. Please take noteofthe minimum machine RAM requirements requiredto run !Shockwave on yourcomputer, also detailed in the Release Note.

What are Shockwave movies?

Shockwave movies are produced by the multimedia authoring application Macromedia Director, an application widely used forpresentations, home shopping, interactive training, cartoon animations and sales kiosks. I'^y include text and graphics, animations, digital video, fades, dissolves and other effects, as well assound tracks.

Shockwavemovies may be authoredon Macintoshor Windowsplatforms, but both versions may be played by IShockwave. Macpeculiarities, suchShadowand Outline fonts, arereplacedif necessary by an equivalent RISC OS font. Running Shockwave movies

The operation of IShockwave is transparentto the user.When you click on a Shockwavemovie on a Web page, as long as it can find it (see the Release Note on where to install plug-ins), the Acom Intemet software plug-ininterface will call IShockwave to play the movie, opening a window in your browser. The movie may bring its own play controls with it.

Ine presence of IShockwave is indicated by its icon appearing on your icon bar.

Quitting iShockwave

IShockwave quits automatically a shorttime after you quit the last Shockwave movie. The actualdelay be altered by editing the Shockwave IRun file. When IShockwave quits, it returns all the memory it was using.

You can also quit IShockwave manually by choosing Quit from the IShockwave icon bar menu. 11 World Wide Web pages What are Web pages?

Web pages are documents created byauthors using a combination ofplain text and a markup language called HTML (HypeiText Markup Language). HTML uses short codes (also known as tags) todefine the structure ofa document (headings, paragraphs, lists, and soon) aswell asgraphical elements and links within the document. An HTML document that is available on the Web is usually known as a Web page.

Clicking on a linkin a Web pagebrings another pagelocated on a localor remote serverto yourcomputer, irrespective oftheserver's geographic location. Pages can contain text, images, sounds, movies, ora c(»nbination of aU these. Creating Web pages

HTML documents areinplain ASCII textformat and youcancreate them using anytexteditor, insertingthe markup codes manually into thetext. Alternatively, you can use anHTML editor such as HTMLEdit, which can make inserting the correct codes easier. HTML tags

HTML uses embedded codes(tags) to designate graphical elements and links. You can createthese codes simply from your keyboard using angled brackets and the slash character. Forexample, thetag presents textinbold letters. An HTML source file containing theexpression Thfe text appears in bold. is displayed on screen in bold. Notice thatthe tag is needed to indicate the end of thebold expression.

HTML consists of many tags likethis which are used both for indicating the structure of a document and caning hyperlinks embedded in the document.

Documentstructuretags can be used to maik the title and body of a document, differentlevels of heading, bulleted lists, paragraph breaks and typographical variations (bold, Italic). Link tags define links to other documents or images. Creating links

Here's an example which creates a link for users to click on:

Acorn Home Page

This link is made up ofthree main elements:

The opening and closing tags. The tag codeA HREP-signals the start of a link, while the closing tag signals the end ofthe link. Thepart of the tag between quotation marks is the URLof the pagebrought by clicking on the link. (See Identifying resources - URLs for more about URLs.) The text following the URL contains the text which appears highlighted on the screen (illthis example, "Acom Home Page"). Looking a! HTML source

You can look at any page's HTML source by choosingthe Display page source option from the button bar. You can then examine all the text and tags used to define the content and style of the page. Identifying resources - URLs

Every single page on the WorldWide Web has an identifier, called a URL, short for Uniform Resource Locator. The URL both locates and uniquely identifies resources on the Web. Using the URL, browsers like Acom Intemet software can find a particular page or file among all the computers connected to the Intemet.

Here's a sample URL: http://www.acorn.com/acorn/Home

The URL is made up of three separate components:

The protocol - the method used for transferring files across a network. The domain name - the name and location ofthe server computer. Hie pathname of the resource - die filename and the name of the directory where the resource is stored.

Protocol

first component in a URL, the protocol, is followed by a colon, for example,http:. It identifies how computers will talk to each other across a network.

Web pages use HTTP (short fcHr HypeiText Transfer Protocol). Other common protocols you might come across in URLs include: file:

When you seefile:at the front ofa URL, it means that the resource is stored on your local system

Mail to:

Starts the mail application to send a mail message to the required destination. ftp: Short for File TransferProtocol, this is an alternativeprotocol for moving files from one computer to another. Forexample, theAcorn FAQ document is available from the following ftp site: ftp://rtfm.mit.edu/pub/usenet/news.answers/acorn/faq gopher:

Another alternative transfer protocol thatallows you to browse for resources viasimple textmenus. For example, the Queensland University of Technology Gopherhas this URL: qopher://gopher2.qut.edu.au/ telnet:

Aprotocol that allows you to login to othercomputers on the Internet. Forexample, you canlog intothe C^^bridge University Libraiy computer and search their catalogue by author, title or subject: telnet://ul.cam.ac.uk/ news:

The protocol used by Usenet news groups. For example, this is the URL for the comp.sys.acom newsgroup, a newsgroup for announcements about Acorn and Acorn products: news:comp.sys.acorn.announce

Domain name

^e second component inthe URL, the domain name, is preceded by two slashes, for example / / www. acorn. com. This part identifies the computerthat stores the informationyou're seeking.

Each server on the Internet has a unique address to distinguish it from all the other servers on the Internet - the domain name. The domain name is broken into several subparts (a host name and zero or more subdomains),with each part separated by a dot (the full stop symbol is pronounced "dot").The subparts are oiganised in a hierarchical sequence from the left (the most specific part ofthe address) to the right (the most general part ofthe address). You can often tell what kind of organisation is operating the serv^ and where the server is located from its address or domain name.

A domain name starts with the name of the server computer, and may also include the name and type ofthe oiganisation providing the server, and the country where the server is located. For example:

www.acorn.com

This is the domain name address for the Acorn Computers Web server, where; www= the name ofthe server computer acorn= the name ofthe company com = the type of organisation (commercial) www,canterbury.ac.nz

This is the domainnamed address for the University of Canterbury Web serverin NewZealand, where www= the name ofthe server computer canterbury= the name ofthe University ac= the type oforganisation (academic)

- New Zealand george.Ibl.gov

This is the domain name for the Lawrence Berkeley National Laboratory Web server in the United States: george= the name ofthe server computer lbl= the name ofthe oiganisaticMi gov= the type of organisation (US Government)

Here are some other common suffixes and their regicMial and organisational affiliations:

^ .CO (commercial) .ac (educational) .uk (United Kingdom) .nl (The Netherlands) .au (Australia) .gov (US government) .com (US commercial) .edu (US educational)

Pathname

The last component ofthe URL is the remote pathname which identifies the location ofthe page on the server. Each segment ofthe pathname is preceded by a single forward slash.

A pathname might identify a page by specifying the name of the file comprising the page (such as /welcome) as well as the name ofone or more subdirectories that store the file (for example,/acornor /acorn/library/ref). Serving pages

You canusetheAcom Internet proxy/cache server to serve yourownpages to other Web users on a local network.

1.First set up a local page cache as describedin Browserconfiguration. 2. Create a Web pagein HTML format. Double-click on 1WebCache, which you wiU find in the same directory as IBrowse, and a directory display will ^pear. Save theHTML file into thedirectorywith a suitable name. 3. Make surethatyou setthefile's expiry time to a suitable length (see Setting the local cache size and expiry times). 4. Restart WebServe. l^aiWeb users will be able to request the page by entering its address in the format: http://node_name/page_pathname wherenode__nameis the IP name of the server. (Notethat URLs are case-sensitive.)

In some limited circumstances,you can also serve pages to remote users, if

1. you have a permanently open phone hne, and 2. your service provider allocates you a fixed BP address (and not a dynamic coie).

In such a case, remote users could access your locally-cached pages by requesting: http: //node_name. servicejprovider/page__pathname

<^re node_name is your Internet name, by which you are known by your service provider (e.g. bashstrt in bashstrt,demon. uk). AppendixA: Acronyms and Smilies

Acronyms

Acronyms are widely used over the Internetin order to save typing time.There is no official list of acronyms, but here are some ofthe more widely used cmes:

AFAIK As FarAs I Know

AFAICT As FarAs I Can Tell

BTW ByThe Way

FWIW For What It's Worth

FYI For Your Information In Any Event lANAL I Am Not A Lawyer

IMO In My Opinion

IMHO In My Humble Opinion

IMNSHO In My Not So Humble Opinion

IMCO In My Consid^ed Opinion low In Other Words

ISTR I Seem To Remember

L8R Later

NRN No Reply Necessary

OTOH On Hie Other Hand ^F,L Rolling On Floor, Laughing ROTFL Rolling On The Floor Laughing

ROTM Right On The Money RSN Real Soon Now[which may be a long time coming]

RTFM Consult The Documentation sriD Stillln The Dark

SO Significant Other (i.e. partner) SysOp System Operator

TIA Thanks In Advance

TIC Tongue In Cheek

TLA Three LetterAcronym (such as this)

TSR Terminate and Stay Resident program

WTT Wordsmith In Training WYSIWYG What You See Is What You Get

YMMV Your Mileage May Vaiy(Your experience may differ)

YKYBHTLW You know you've been hacking too long when...

Smiiies

Because of the limitations of written communication, where the tone ofvoice is not available to the reader, there is widespread use of ^smilies' (or'emoticons') in postings. Themost common of these is: -) (3 smiling face - look at it sideways). This is meant to show that the writer is smiling when she wntes, and no ottence IS intended 1be intemationai Internet audience covers a wide range of cultures and familiarities with the English language, so opportunities tor misunderstanduigs to anse are frequent - Anglo-^iaxonirony is one such pitfall - so smiiies can be useful.

Other smiiies are: ^ Winky smiley. Userjust made a flirtatious and/or sarcastic remark. More of a "don't hitme ' ' for what Ijust said" smiley Frowning smiley. User did not like that last statementor is upset or depressed about something : -1 Indifferent smiley. Better than a frowning smiley, but not quite as good as a happy smiley = :-0 Scary : -P Sticking tongue out Here are some somewhat less common smiiies: %-) User has been staring at a green screen for 15 hours straight.

User is drunk User is wearing sunglasses

B:-) Sunglasses on head

.:•) User wears normal glasses B-) User wears horn-rimmed glasses

{:-) User wears a toupee }:•( Toupee in an updraft User is crying User is so happy, she is crying User is screaming User wears braces (US English - i.e. on her teeth) Appendix B: Writing Acom Internet Command Scripts introduction

Oneof the most useful facilities for setting up anAcom Intemet system is its scripting language. This language gives you the flexibility toconfigure it so that it can operate with a wide range ofconnection and authentication interfaces used by Intemet service providers, and automate theprocedure for connecting yoursystem to the Intemet so that yourmachine candownload youremail andUSENET News at any configured time ofday.

This Appendix leads youthrough a typical script, and contains further details about IPallocation inAcom Intemet software andits requirements regarding protocols which must be supported by service providers, in addition to supplying a reference to theAcomIntemetsoftware script command set.

Protocols and interfaces

Currently, Acom Intemet software is capable of transmitting and receiving BP datagrams as SLIPpackets, PPP packets or "unwrapped" IP packets.

SLIPprovides a point-to-point connection between twodevices for the transmission of Intemetdatagrams; thedevices canbe either twocomputers, or a computer andanIntemet router. SLIP modifies a standard Intemet datagram by appending a specialSLIP END characterto it, which allows datagramsto be distinguished as separate when transmitted serially.

PPP provides a point-to-point connection as well. The advantage PPP has over SLIP is that it can compress the header information (which contains such information as the intended destination ofthe packet), and test ^ integrity of inter-system connections, rerouting packets where Expropriate. PPP will also take care of iiiuch of the connection configuration, thus making life easier for Acom Intemet software script authors.

The Acom Intemet PPP driver supports the "block driver" interface, which has been available for some time as a Freeware interface specification and conformant device driver set. This now means that, in addition to the intemal serial port, third party devices such as high-speed dual soial port cards may be used which enable pre-Risc PC machines to exchange data with a modem at rates >19200 baud. Whichever physical interface is used, the PPP driver refers to it as "pppO" (PPP port 0).

Ifyou have a direct Ethemet connection to the Intemet (e.g. via ISDN), Acom Intemet software can make use ofthis as well.

The use of SLIP or PPP cmly affects the fundamental IP layer, and is therefore transparent to the upper-layer protocols; hence service-oriented protocols such as SMTP (email), NNTP (USENET News), FTP (File Transfer Protocol), HTTP (World Wide Web) and other equivalent-layer protocols such as telnet will all work correctly over SLIP or PPP. Otherfactors to bearin mind arethatthe configuration ofAcorn Internet software is subtly different depending on whether your provider allocates you a fixed IPaddress orhas dynamic IPallocation (in which your IPaddress is determined as part ofeach logon procedure), and that the Point ofPresence (PoP) you plan to use supports modem speeds up tothe maximum rate supported by your own modem, subject tothe limitations imposed bythe serial port (see Acorn Customer Services Application Note 234 for further details). Anatomy of a logon script

The following paragraphs provide a line-by-line dissection ofa typical Acom Internet software logon script; lines printed in Courier comprise thescript itself. Thescripts themselves arestored with theleafname "Script" inthedirectory relevant to the service provider inthe !Connect.Providers hierarchy; for example, the script forDemon Internet Services is stored as "!Connect.Providers.Demon.Script". Theremaining files in the !Connect. directory contain details of the telephone numbers of the currently-known l^Si^ts ofPresence (PoPs) used by each provider.

jjfDemon Internet SLIP

This line is a comment, as it starts with a #. In this case, the line just signifies that this script is intended for use whenconnecting to DemonInternet Services, in this case using the SLIPprotocols. Comments canbe freely distributed throughout the script.

retry 5 5 10

Set the connection retry system so that connection is attemptedfive times.The delay betweenthe first and second attempts is five seconds, after which it tries at 10 second intervals.

NewsRetry 50 ^i;sthe connection retry system to attempt up to 50 retries when contacting the USENET News server.

*rmensure slip 2.07 rmload System:Modules.Network.SLIP

*rmensure slip 2.07 Error Slip version 2.07 or later is required

These lines ensure that the correct version ofthe SLIP driver is loaded.

If you are using the PPP driver, replace these lines with:

*rmensure PPP 1.02 rmload System:Modules.Network.PPP

*rmensure PPP 1.02 Error PPP version 1.02 or later is required

+ifconfig -e slO down This switches the SLIPdriver off; all transactions whichtake place betweenthis line of the script and a line containing ifconfig -e slO uptake place using "ordinary" V.nn modem protocols andflow control. ThePPP driver initialises in a switched-off state, so this line can be omitted in the case ofPPP being used. The use of a "+"as opposed to a "*"to prefixthe command signifies that,if the command should fail to execute successfully, it should fail silently andhence allow the login script to continue executing rather than aborting and reporting an error.

SerialSetup

This initialises the serial port to the appropriate baud rate, word length, parity etc.

Timeout 10

This is used by the Wait conunand; a Wait is now configuredto time out (reporting an error,terminating the script and closing the serial connection) 10 seconds after it is encountered.

Aoort Busy

Abort Carrier

Abort incprrect

Abort tone

If any ofthe strings following "Abort" are sent to the computer by the modem during the next phase of establishing the connection, the script will close the connection to the modem and terminate.

Echo

Tells the system to start copying incoming data to its logging system.

Send ATZ

Sends the Hayes command string to the modem to reset it to its default configuration.

Wait OK

Pauses until the string "OK" is sent to the computer by the modem, or generates an error, closes the connection and terminates the script if "OK" is not received before 10 seconds have elapsed.

Init

Sends the configured initialisation string to the modem.

Wait OK As above.

Timeout 120

Dial

Resets the Wait timeout to 120 seconds, and uses the configured dialling method to contact the service provider.

Wait ogin:

Waits until the string "ogin:"is received, or until 120 secondshave elapsed. As the "L" at the front of "Login:" varies from upperto lower case between serviceproviders (and occasionally betweenPoPs run by the same service provider), it has been omitted from the test.

Timeout 60

Login

Modified the timeout period again, and sends the configured login name terminated by a carriage return.

Wait assword:

Password

Waits for the tail end ofthe "Password:" prompt from the service provider, and sends the configured password in response.

Wait ocol:

idle=120,SLIP

This is a part of the connection dialogue which appears to be operational for a number of service providers, although the inclusion of the "idle" response seems unique to Demon Internet Services; the service provider requests details ofthe protocol you will be running once your full IP connection is brought up. "ocol:" is the tail-end of Demon's "Protocol:" query; everything following the "Send" in the line below it is sent verbatim in response. If you were using the PPP driver you would have the line

Send idle=120,PPP instead. You may also wish to "fine-tune" the timeout value.

Wait ddress:

GetIP This operation will, if dynamic BP allocation is enabled, configure your machine to usetheIPaddress returned for this session bythe service provider (see below); otherwise, if youhave a static BP address, it will be ignored.

Wait HELLO

In the case of Demon InternetServices, "HELLO" signifies that the logon and configuration procedureis complete; from hereon, data sentto youby the service provider will comprise SLIPpackets. Your own service provider mayuse a different string; check the documentation accompanying yourcontract with them for details.

Config slO

This sets up the broadcast address, netmasketc whichwill be usedby the SLIPinterface during the session

-ij^config -e slO up

This line activates the SLIP driver, bringing you fully online.

Route

This sets up the IP routing system between you and your service provider, taking into account which PoP you are using and which modem you are connectedto at that PoP automatically.

If you are using the PPP driver you can ignore the above three commands. Instead you need to replace then with the following two lines.

*pppconnect InterrnalPC 0 noipdefault defaultroute crtscts modem asyncmap 0 getifaddr pppO

tells the PPP module to connect to the device "IntemalPC" (which is the internal serial port using a standard PC cable to connect to the modem) using the speed already defined on the serial port, setting up all that is needed automatically. If you are using an Acom-style cable (as described in Acorn Customer Services Application Note 234, and intended for use with systems fitted with 6551 serial controller ICs) "IntemalPC" should be replaced with "Intemal". Forexternal and third party high speed serial adaptors, details of the appropriate interface name should be supplied with the interface. Your modem must be configured to use RTS/CTS, to hang up when DTR is dropped and to make DCD follow the state of the line.

The remaining parameters used by *pppconnect are detailed, along with all other *pppconnect options, in pppconnect for RISC OS. Writing your Own Scripts

The script above is designed to work with Points of Presence (PoPs) run by Demon Intemet Services; if you are using a different service provider, youmay well findthatthe detail of the logon procedure differs from the one above, or you may haveto re-tune your timeoutthresholds. Upto the point wherethe service provider is dialled, however, it should be possible to duplicate the script "asis" depending upon the reaction ofyour modem to standard Hayes commands.

The details supplied by your service provider when youtake out yourcontract withthem should provide sufficient information to writea script which will operate with theirlogon procedures, however tuning the timeouts can be a fine art and is best judged by experience. Handling Dynamic IP Allocation

Acorn Intemet softwareis capable of handlingthe dynamic IP address allocation systems used by some serviceproviders; if the IP address in the configuration file is left blank or set to Auto,the insertionof GetIPat the appropriate point in the auto-logon script will enable the IP address of your machineto be configured according to the dotted decimal IP address sent by the service provider.

It me IP address in the configuration file were left blank, the new IP address as returned by the service provider is put in the appropriate field in the configuration file and the file is then re-saved.

K the IP address field in the configuration file contains the string "Auto", the IP address returned by the serviceprovider is used for the duration of the session,but the contents of the configurationfile are not altered.

If the IP address in the configuration file already has an IP address in it, the GetIP command is ignored. Scripting Language Command Set

Abort

?^.tax: Abort

This adds the specified string to the list of abort strings. If any string in this list is received fi*om the service provider, the script is aborted with the error "Script aborted ()". Acorn Intemet software will then try to re-establish the connection to the service provider, in accordance with the parameters passed to the Retry command (q.v.)

Config

Syntax: Config

Configures the named interface as a machine-to-provider link connecting the configured IP address with the configured gateway.

Dial Syntax; Dial

SendeitherATDT or ATDP (Hayes modem commands for tone and pulsedialling respectively) to the modem, depending on the configured dial method, followed by the configured telephone number.

Echo

Syntax: Echo

Sets the server to echo incoming data to the server log.

GetlFAddr

Syntax: GetlFAddr

A^mpts to determine the IP address of the interface whenusing dynamic IP allocation. The conunandwaits for five seconds,during which time the remote system shouldreply with the address; if this does not happen, the command times out, generating an error and aborting the logon script.

GetiP

Syntax: GetIP

If the IP address in the configuration file is left blank or set to Auto, this command looks in the input from the service provider for an BP address and configures it as the IP address to use for the local machine (giving the functionality of dynamic IP allocation).

Ifthe IP address in the configuration file was left blank, the new IP address as returned by the service provider is put in the appropriate field in the configuration file and the file is then re-saved.

Ifthe IP address in the configuration file already has an IP address in it, the GetBP command is ignored.

Hangup

Syntax: Hangup

This command waits for one second, then sends "+++" to the modem, followed by another one second pause. It then sends the configured hangup string to the mod^i.

•nit

Syntax: I nit

This command sends the configured init string to the modem. Login

Syntax: Login

This command sends the configured localsystem nameto the serviceprovider, followed by a carnage return.

News

Retry Syntax: NewsRetry

Sets the number of retries to use when attemptingto connectto the USENETNews server.

NoEcho

S^ax: NoEcho

Stops the server from echoing incoming data in the system log.

OS Command

Syntax: *

Passes a command to the RISC OS Supervisor for execution.

Password

Syntax: Password

S^^s the configured password followed by a carriage return.

Retry

Syntax: Retry x y z

Sets the number oftimes the system attempts to make a connection to the service provider. x= number of times to retry before failure y= time in seconds between first and second attempts z= time in seconds between second and subsequent attempts

Route Syntax: Route

Sets a default IP route through the configured gateway address.

Send

Syntax: Send

Sends the attached string to the modem, terminated by a carriage return.

SerialSetup

Syntax: SerialSetup

Configures the serial port to match the configured setup parameters.

1 imeout

Syntax: Timeout

Sets the delay in seconds to n before a wait times out.

Wait

Syntax: Wait

Waits for string to be received from the service provider. The string is case sensitive. If the string is not received within the time set by the Timeout command (q.v.) the script will terminate with the error "Script timed out." pppconnect for RISC OS

Synopsis

*PPPConnect [[:]] [speed] [options]

Description

The Point-to-Point Protocol (PPP) provides a method for transmitting datagrams over serial point-to-point links. PPP is composed of three parts: a method for encapsulating datagrams over serial links, an extensible Link Control Protocol (LCP), and a family of Network Control Protocols (NCP) for establishing and configuring different network-layer protocols.

The encapsulation schemeis providedby driver code in the kernel, pppd providesthe basic LCP, authentication support, and an NCP for establishing and configuring the Internet Protocol (BP) (called the IP Control Protocol, IPCP).

Frequently used options

[:]

Loadthe namedblockdriver from SerialDev:Modules, and use the givenport for communication. If this is notspecified, thepreviously used driver will beused. ThePPP module contains theInternal driver, which will be used ifthis option is never specified.

Set the baud rate to< speed>. The availablespeedsdepend on the device you are using. If not specified, it will use the current setting ofthe chosen driver.

^^ncmap

Set the async character map to

Require the peer to authenticate itself before allowing network packets to be sent or received, crtscts

Loc hardware flow control (i.e. RTS/CTS) to control the flow of data on the serial port, xonxoff

Use software flow control (i.e. XON/XOFF) to control the flow ofdata on the serial port. If neither this option nor the previous is used, the current state ofthe driver will be used

-crtscts

A synonym for xonxoff. defaultroute

Add a default route to the system routing tables, using the peer as the gateway, when IPCP negotiation is successfully completed. This entry is removed when the PPP connection is broken. escape xx,yy,...

Specifies thatcertain characters should be escaped ontransmission (regardless of whether thepeerrequests them tobeescaped with its async control character map). The characters tobeescaped are specified asa list of hexnumbers separated by commas. Note thatalmost any character canbe specified fortheescapeoption, unlike theasyncmap option which only allows control characters tobespecified. Thecharacters which may not be escaped are those with hex values 0x20 - 0x3f or 0x5e. file

Read options from file (the format is described below), mru

Set the MRU [Maximum Receive Unit] value to for negotiation,pppd will ask the peer to send packets (^£^0 more than bytes. The minimum MRU value is 128. The default MRU value is 1500. Avalue of 2>o is recommended for slow links (40 bytes for TCP/IP header + 256 bytes of data). netmask

Set the interface netmask to , a 32 bit netmask in "decimal dot" notation (e.g. 255.255.255.0). passive

Enables the "passive"option in the LCP. With this option, pppd will attemptto initiate a connection; if no reply is received from the peer, pppd will then just wait passively for a valid LCP packet from the peer (instead ofexiting, as it does without this option). silent

this option, pppd will not transmit LCP packets to initiate a connection until a valid LCP packet is received from the peer (as for the "passive" option with old versions of pppd).

Options

;

Set the local and/or remote interface IP addresses. Either one may be omitted. The IP addresses can be specified with a host name or in decimal dot notation (e.g. 150.234.56.78). The default local address is the (first) IP address of the system (unless the noipdefault option is given). The remote address will be obtained from the peer if not specified in any option. Thus, in simple cases, this option is not required. If a local and/or remote IP address is specified with this option, pppd will not accept a different value from the peer in the IPCP negotiation, unless the ipcp-accept-local and/or ipcp-accept-remote options are given, respectively. -all

Don'trequest or allownegotiation of any options for LCP and IPCP (usedefaultvalues).

-ac

DisableAddress/Control compression negotiation (use default,i.e. address/control field disabled).

-am

Disable asyncmapnegotiation (use the default asyncmap,i.e. escape all control characters)

-as

Same as asyncmap

Disable IP address negotiation (with this option, the remote IP address must be specified with an option on the command line or in an options file).

-mn

Disable magic number negotiation. With this option, pp^d cannot detect a looped-back line.

-mru

Disable MRU [Maximum Receive Unit] negotiation (use default, i.e. 1500).

-P

Saine as the passive option.

-pc

Disable protocol field compression negotiation (use default, i.e. protocol field compression disabled).

+ua

Agree to authenticate using PAP [Password Authentication Protocol] ifrequested by the peer, and use the data in file

for the user and password to send to the peer. The file contains the remote user name, followed by anewline, followed by the remote password, followed by a newline. This option is obsolescent.

+pap Require the peer to authenticate itself using PAR

-pap

Don't agree to authenticate using PAP.

+chap

Require the peerto authenticate itselfusing CHAP [Cryptographic Handshake Authentication Protocol] authentication.

-chap

Don't agree to authenticate using CHAP.

Disable negotiationof Van Jacobson style IP header compression. This is the default above line speeds of 19200 baud, as VanJacobson suffers from diminishing returns at high line speeds, and can be badly affectedby a poor link. The main aim of VJ compressionis to improve responsiveness of interactivetraffic, eg typing via Telnet, over slow lines. It will not generally speed up file transfers, such as FTP.

+vj

Enable negotiation of VanJacobson stype IP header compression. This is the default at line speeds of 19200 baud or below. domain

Append the domain name to the local host name for authentication purposes. For example, if gf^.ostnameO letums the name porsche, but the fully qualified domain name is porsche.Quotron.COM, you would use the domain option to set the domain name to Quotron.COM modem

Use the modem control lines, ie signal to the modem using DTR, and check for hang-ups via DCD. local

Don't use the modem control lines, mtu

Set the MTU [Maximum Transmit Unit] value to . Unless the peer requests a smaller value via MRU negotiation, pppd will request that the kernel networking code send data packets ofno more than n bytes through the PPP network interface. name

Set the name ofthe local system for authentication purposes to . user

Set the user name to use for authenticating this machine with the peer using PAPto . usehostname

Enforce the use of the hostname as the name of the local system for authenticationpurposes (overrides the name option). remotename

Set the assumed name ofthe remote system for authentication purposes to . noipdefault

Disablesthe default behaviour when no local IP addressis specified,which is to determine (if possible) the local BP address from the hostname. With this option, the peer will have to supply the local IP address during IPCP negotiation(unless it specifiedexplicitly on the commandUne or in an options file).

Icp-echo-interval

If this option is given, pppd will send an LCP echo-requestframe to the peer every n seconds. Under Linux, the echo-requestis sent when no packets have been received from the peer for n seconds. Normallythe peer should respond to the echo-request by sending an echo-reply. This option can be used with the Icp-echo-failure option to detect that the peer is no longer connected. l'^-echo-failure

If this option is given, pppd will presume the peer to be dead if n LCP echo-requests are sent without receiving a valid LCP echo-reply. If this happens, pppd will terminate the connection. Use ofthis option requires a non-zero value for the Icp-echo-interval parameter. This option can be used to enable pppd to terminate after the physical connection has been broken (e.g., the modem has hung up) in situations where no hardware modem control lines are available.

Icp-restart

Set the LCP restart interval (retransmission timeout) to seconds (default 3).

Icp-max-terminate

Set the maximum number ofLCP terminate-request transmissions to (default 3). Icp-max-configure

Set the maximum number of LCP configure-request transmissions to (default 10). lop-max-failure

Set the maximumnumber of LCP configure-NAKs returned before starting to send configure-Rejects instead to (default 10). ipcp-restart

Set the IPCP restart interval (retransmission timeout) to seconds (default 3). ipcp-max-terminate

Set the maximum number ofIPCP terminate-request transmissions to (default 3). ipcp-max-configure

Set the maximum number ofDPCP configure-request transmissions to (default 10). ipcp-max-failure

Set the maximum number ofIPCP configure-NAKs returned before starting to send configure-Rejects instead to (default 10). pap-restart

Set the PAP restart interval (retransmission timeout) to seconds (default 3). p^-max-authreq

Set the maximum number ofPAP authenticate-request transmissions to (default 10). chap-restart

Set the CHAP restart interval (retransmission timeout for challenges) to seconds (default 3). chap-max-challenge

Set the maximum number ofCHAP challenge transmissions to (default 10). chap-interval

Ifthis option is given, pppd will rechallenge the peer every seconds. ipcp-accept-local

With this option, pppd will accept thepeer's idea ofour local IPaddress, even ifthelocal BP address was specified in an option. ipcp-accept-remote

With this option, pppd will accept the peer's idea ofits (remote) IPaddress, even iftheremote IPaddress was specified in an option. Options flies

Options canbe taken from files as well as the command line. PPPreads options from the files InetDbaseiPPP.options before looking at the command line. Anoptions fileis parsed intoa series of words, delimited by whitespace. Whitespace canbe included in a wcwrd by enclosing the word in quotes ("). A b^slash quotes thefollowing character. Ahash (#)starts a comment, which continues until theendof the line.

Authentication

PPPprovides system administrators with sufficient access control that PPP access to a servermachine can be provided to legitimate users without fearof compromising the security of the serveror the network it's on. In part this is providedby the InetDbase:PPP.options file, wherethe administrator can place optionsto require authentication wheneverPPP is run, and in part by the PAPand CHAPsecrets files, where the administrator can restrict the set of BP addresses which individual users may use.

The default behaviour of PPP is to agree to authenticateif requested,and not to require authentication from the peer. However, PPP will not agree to authenticate itself with a particular protocol ifit has no secrets M^ch could be used to do so.

Authentication is based on secrets, which are selected from secrets files (InetDBaserPPRPAPSecrets for PAP, InetDBase:PPP.CHAPSecret for CHAP). Both secrets files have the same format, and both can store secrets for several combinations of server (authenticating peer) and client (peer being authenticated). Note that pppd can be both a server and client, and that differentprotocols can be used in the two directionsif desired.

A secrets file is parsed into words as for a options file. A secret is specified by a line containing at least three words, in the order client, server, secret. Any following words on the same line are taken to be a list of acceptable IP addresses for that client. If there are only three words on the line, it is assumed that any BP address is OK; to disallow all IP addresses, use Ifthe secret starts with an ^@', what follows is assumed to be the name ofa file from which to read the secret. A as the client or server name matches any name. When selecting a secret, pppd takes the best match, i.e. the match with the fewest wildcards.

Thus a secrets file contains both secrets for use in authenticating other hosts, plus secrets which we use for authenticating ourselves toothers. Which secret touse is chosen based on the names ofthe host (the local name') andits peer (the"remote name'). The local name is set as fcdlows: ifthe usehostname option isgiven, then the local name isthe hostname ofthis machine (with the domain appended, if given) elseif the name option is given, thenusethe argument of thefirst name option seen else if the local IP address is specified with a hostname,then use that name else use the hostname ofthis machine (with the domain appended, ifgiven)

When authenticating ourselves using PAP, there is also a "usemame' which is thelocal name bydefault, but can be set with the user option or the +ua option.

The remote name is set as follows: ii uie remotenameoptionis given, then use the argumentof the last remotenameoption seen else if the remote IP address is specified with a hostname, then use that host name else the remote name is the null string "".

Secrets are selected from the PAP secrets file as follows:

For authenticating the peer, lookfor a secret with client = usemame specified in the PAP authenticate-request, and server == local name. For authenticating ourselves to the peer, look for a secret with client == our usemame, server =

remote name.

When authenticating the peer withPAP, a secretof "" matches any password supplied by the peer. If the pf^word doesn't match the secret, thepassword isencrypted using crypt() and checked against thesecret again; thus secrets for authenticating the peer can be storedin encrypted form. Thus,the system administrator can set up the PAP secrets file to allowPPP access onlyto certain users, andto restrictthe set of IP addresses that each user can use.

Secrets are selected from the CHAP secrets file as follows:

For authenticating the peer, look for a secret with client = name specified in the CHAP-Response message, and server == local name. For authenticating ourselves to the peer, look for a secret with client == local name, and server == name specified in the CHAP-Challenge message.

Authentication must be satisfactorily completedbefore IPCP (or any other NetworkControlProtocol)can be started. If authentication fails, pppd will terminated the link (by closing LCP). IfIPCP negotiates an unacceptable IP address for the remote host, EPCP will be closed. IP packets can only be sent or received when IPCP is open. In some cases it is desirable to allow some hosts which can't authenticatethemselvesto connect and use one of a restricted setof IP addresses, evenwhen the local hostgenerally requires authentication. If thepeer refuses toauthenticate itself when requested, pppd takes that as equivalent to authenticating with PAP using the empty string for the usemame and password. Thus, by adding aline tothe pap-secrets file which specifies the empty string for the client and password, itis possible to allow restricted access to hosts which refuse to authenticate themselves. Routing

When IPCP negotiation is completed successfully, pppd will inform the kernel ofthelocal and remote BP addresses for the ppp interface. This is sufficient to create a host route tothe remote end ofthe Knk, which will enable thepeers to exchange IPpackets. Communication with other machines generally requires further modification to routing tables and/or ARP (Address Resolution Protocol) tables. In some cases this willbe done automatically through the actions of the routed or gateddaemons, but in most cases some fpa^her intervention isrequired.

Sometimes it is desirable to add a default routethrough the remotehost, as in the caseof a machine whose only connection to theInternet is through thepppinterface. Thedefauhroute option causes PPPto create such a default route when BPCP comes up, and delete it when the link is terminated.

In some cases it is desirable to useproxy ARP, for example on a server machine connected to a LAN, in order to allow other hosts to communicate with the remote host.The proxy-arpoption causespppd to look for a network interface on the same subnet as the remote host (an interface supporting broadcast and ARP, which is up andnota point-to-point or loopback interface). If found, PPPcreates a permanent, published ARP entry with the IPaddress oftheremote host andthehardware address ofthenetwork interface found. (Not implemented yet) Examples

In the simplestcase,you can connectthe serialports of two machines and issue a commandlike

*PPPConnect internalPC 9600 passive

If you are using a modem, you will need to run a dialler, such as Chat,to make the initial connection. Ifyour serial connectionis any more complicatedthan a piece of wire, you may need to arrange for some control characters to be escaped. In particular, it is often useful to escs^e XON (^Q) and XOFF C^S), using asyncmap aOO(X). If you need to authenticate yourself to the remote end, using PAP, you would use a command like

*PPPConnect 115200 user m.jones and have a line in your PAP secrets file m.jones * abcdefg meaning that userm.jones should be authenticated to anyhost withthe password abcdefg.

To close the link, issue the command

*PPPDisconnect

Diagnostics

The contents of all control packets sent or received are logged, thatis, all LCP, PAP, CHAP or BPCPpackets. This can be usefulif the PPP negotiation does not succeed. The log can be displayedusingthe *PPPLog command. The *PPPInfo command provides standard network driver statistics.

Fiies

I^tDBas0:PPP. IP-Up

Aprogram or scriptwhichis executed whenthe link is available for sending andreceiving IP packets (that is, IPCP has come up). It is executed with the parameters interface-name driver speed local-IP-address remote-IP-address.

This file is restricted in what it can do. In particular it should not start a new application(eg running ifconfig).

InetDBaserPPP.IP-Down

A program or script which is executed when the link is no longer availablefor sendingand receiving IP packets.This script can be used for undoing the effects of the InetDBase:PPP.IP-Up script. It is invoked with the same parameters as the ip-up script. The same restrictions apply.

I'^tDBase:PPP. PAPSecrets

Usemames, passwords and IP addresses for PAP authentication.

InetDBase:PPP.CHAPSecret

Names, secrets and BPaddresses for CHAP authentication.

InetDBase:PPP.Options

System default options for PPP, read before ccanmand-line options.

Notes

Ifyou wish to check the state of the PPP connection from an application, there are two things you need to check.

Using socketioctl (SIOCGIFFLAGS) will tell you whetherthe IP layer is up (the IFF_UPflags).

To tell whether the PPP daemon is actually activeyou will needto usethe PPP_Stats SWT to examine the running flag; the IFF_RUNNING flag from the socketioctl does not correctly indicatethe state of the daemon. Bibliography

RFC1144

Jacobson, V. Compressing TCP/DP headers for low-speed serial 1990 February.

RFC1321

F^st, R.The MD5 Message-Digest Algorithm. 1992 April.

RFC1332

McGregor, G. PPP Internet Protocol Control Protocol (IPCP). 1992 May.

RFC1334

Lloyd, B.; Simpson, W.A. PPP authentication protocols. 1992 October.

RFC1548

Simpson, W.A.The Point-to-Point Protocol (PPP). 1993 December.

1^1549

Simpson, W.A. PPP in HDLC Framing. 1993 December.