Sockets and Client/Server Communication
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BOROUGH of MANHATTAN COMMUNITY COLLEGE City University of New York Department of Computer Information Systems Office S150/Phone: 212-220-1476
BOROUGH OF MANHATTAN COMMUNITY COLLEGE City University of New York Department of Computer Information Systems Office S150/Phone: 212-220-1476 Web Programming II Class hours: 2 CIS 485 Lab hours: 2 Spring 2012 Credits: 3 Course Description: This course will introduce students to server-side web programming. Emphasis is placed on database connectivity in order to solve intermediate level application problems. Students will be tasked with web projects that facilitate understanding of tier design and programming concepts. The overall goal of this course is to create a shopping cart application with a login and database component. Prerequisites/Co-requisite: Basic Skills: ENG 088, ESL 062, ACR 094, MAT 012/051; CIS 385 Web Programming I Learning Outcomes and Assessment After completing this course, students will be able to: Outcome: Demonstrate the use of a database with server-side scripting Assessment: Lab exercises and exam questions Outcome: Demonstrate the use a Cookie and Session manager with server-side scripting Assessment: Final project, lab exercises and exam questions Outcome: Develop a database-driven website Assessment: Lab exercises Outcome: Design and develop a shopping-cart application with a login and database component Assessment: Final Project General Education Outcomes and Assessment Quantitative Skills – Students will use quantitative skills and concepts and methods of mathematics to solve problems Assessment: Use formulas and concepts of mathematics to solve problems in programming assignments Information and Technology -
Libioth (Slides)
libioth The definitive API for the Internet of Threads Renzo Davoli – Michael Goldweber "niversit$ o% Bolo&na '(taly) – *avier "niver#it$ (Cin!innati, "SA) ,irt-alS.-are Micro/ernel DevRoo0 1 © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 (nternet of Thread# (IoTh) service1.company.com → 2001:1:2::1 service2.company.com → 2001:1:2::2 host.company.com→11.12.13.14 processes service3.company.com → 2001:1:2::3 2 © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 IoTh vs Iold What is an end-node o% the (nternet4 (t depends on what is identified b$ an (P addre##. ● (nternet o% 1hreads – (oTh – 7roce##e#8threads are a-tonomou# nodes of the (nternet ● (nternet o% 9e&ac$ Devi!es 'in brie% (-old in this presentation) – (nternet o% :ost# – Internet of ;etwork Controller#. – (nternet o% ;a0e#5a!e# 2 © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 7,M – IoTh - </ernel 4 © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 7,M – IoTh - </ernel ● icro/ernel, Internet o% Threads, Partial Virtual a!hines have the co00on goal to create independent code units i05lementing services ● 1hey are all against monolithic i05lementation# ● 1he challenge o% this talk is to !reate !ontacts, e>5loit paralleli#0#+ that allow to share res-lts, A7I, code. = © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 Network Sta!/ ● API to application layer TCP-IP stack TCP UDP IPv4 IPv6 ICMP(v4,v6) ● API (NPI) to data-link – (e.g. libioth uses VDE: libvdeplug) ? © 2021 Davoli-Goldweber libioth. CC-BY-SA 4.0 IoTh & </ernel User process User process TCP-IP stack TCP UDP TCP/IP stack process IPv4 IPv6 ICMP(v4,v6) TCP-IP stack TCP UDP IPv4 IPv6 ICMP(v4,v6) Data-link network server Data-link network server @ © 2021 Davoli-Goldweber libioth. -
DLCGI Advanced Uses
DLCGI Advanced Uses Using DLCGI to achieve single sign-on with The Diver Solution In situations where authentication to DiveLine needs to be integrated with an existing authentication scheme, we provide "DLCGI", the DiveLine-Common Gateway Interface interfacing module. The "Common Gateway Interface" is a standard for interfacing external scripts and programs with a web server. How DLCGI works When dlcgi.exe is executed by the webserver, in the context of a user that the web server has already authenticated, it obtains a limited-lifetime one-time password from DiveLine. This password can be passed, via web page redirects, custom web page scripting, etc., to DivePort, NetDiver, or even ProDiver to allow the user to login. The typical strategy for using DLCGI is: 1. Configure DiveLine to accept DLCGI requests from your webserver. 2. Install dlcgi.exe in a scripts directory (e.g. /cgi-bin/) on your CGI-compliant webserver (e.g. IIS, Apache). You configure the name of your DiveLine server and other parameters using dlcgi.cfg in the same directory as the executable. 3. Restrict access to this script so that the webserver will only execute it when the user has already authenticated (e.g. Domain account). Typical uses • DivePort: Users go to the DivePort site, and are redirected to another URL for authentication. That URL, which runs dlcgi.exe, redirects the user back to the DivePort URL with a one-use authentication token. • ProDiver: When ProDiver connects to DiveLine, if configured with a DLCGI URL, it will access the URL in "raw" mode (see below) to obtain a parse-able result file containing a one-use DiveLine authentication token. -
Leukemia Medical Application with Security Features
Journal of Software Leukemia Medical Application with Security Features Radhi Rafiee Afandi1, Waidah Ismail1*, Azlan Husin2, Rosline Hassan3 1 Faculty Science and Technology, Universiti Sains Islam Malaysia, Negeri Sembilan, Malaysia. 2 Department of Internal Medicine, School of Medicine, Universiti Sains Malaysia, Kota Bahru, Malaysia. 3 Department of Hematology, School of Medicine, Universiti Sains Malaysia, Kota Bahru, Malaysia. * Corresponding author. Tel.: +6 06 7988056; email: [email protected]. Manuscript submitted January 27, 2015; accepted April 28, 2015 doi: 10.17706/jsw.10.5.577-598 Abstract: Information on the Leukemia patients is very crucial by keep track medical history and to know the current status of the patient’s. This paper explains on development of Hematology Information System (HIS) in Hospital Universiti Sains Malaysia (HUSM). HIS is the web application, which is the enhancement of the standalone application system that used previously. The previous system lack of the implementation of security framework and triple ‘A’ elements which are authentication, authorization and accounting. Therefore, the objective of this project is to ensure the security features are implemented and the information safely kept in the server. We are using agile methodology to develop the HIS which the involvement from the user at the beginning until end of the project. The user involvement at the beginning user requirement until implemented. As stated above, HIS is web application that used JSP technology. It can only be access within the HUSM only by using the local Internet Protocol (IP). HIS ease medical doctor and nurse to manage the Leukemia patients. For the security purpose HIS provided password to login, three different user access levels and activity log that recorded from each user that entered the system Key words: Hematology information system, security feature, agile methodology. -
Improving Networking
IMPERIAL COLLEGE LONDON FINALYEARPROJECT JUNE 14, 2010 Improving Networking by moving the network stack to userspace Author: Matthew WHITWORTH Supervisor: Dr. Naranker DULAY 2 Abstract In our modern, networked world the software, protocols and algorithms involved in communication are among some of the most critical parts of an operating system. The core communication software in most modern systems is the network stack, but its basic monolithic design and functioning has remained unchanged for decades. Here we present an adaptable user-space network stack, as an addition to my operating system Whitix. The ideas and concepts presented in this report, however, are applicable to any mainstream operating system. We show how re-imagining the whole architecture of networking in a modern operating system offers numerous benefits for stack-application interactivity, protocol extensibility, and improvements in network throughput and latency. 3 4 Acknowledgements I would like to thank Naranker Dulay for supervising me during the course of this project. His time spent offering constructive feedback about the progress of the project is very much appreciated. I would also like to thank my family and friends for their support, and also anybody who has contributed to Whitix in the past or offered encouragement with the project. 5 6 Contents 1 Introduction 11 1.1 Motivation.................................... 11 1.1.1 Adaptability and interactivity.................... 11 1.1.2 Multiprocessor systems and locking................ 12 1.1.3 Cache performance.......................... 14 1.2 Whitix....................................... 14 1.3 Outline...................................... 15 2 Hardware and the LDL 17 2.1 Architectural overview............................. 17 2.2 Network drivers................................. 18 2.2.1 Driver and device setup....................... -
Getting Started Guide with Wiz550web Getting Started Guide with Wiz550web
2015/02/09 17:48 1/21 Getting Started Guide with WIZ550web Getting Started Guide with WIZ550web WIZ550web is an embedded Web server module based on WIZnet’s W5500 hardwired TCP/IP chip, Users can control & monitor the 16-configurable digital I/O and 4-ADC inputs on module via web pages. WIZ550web provides the firmware & web page examples for user’s customization. This page describes the following topics: ● Product Preview ● Hello world ❍ Product contents ❍ SD card initialization ❍ Data flash initialization ❍ Serial debug message ● WIZ550web Basic operations and CGI ● Basic Demo Webpage ● Examples for WIZ550web customization Users can download the following source codes from the 'WIZ550web GitHub Repository' ● Firmware source code (The projects for Eclipse IDE) ❍ Application / Boot ● Demo webpage WIZ550web GitHub Repository https://github.com/Wiznet/WIZ550web WIZ550web GitHub Page http://wiznet.github.io/WIZ550web Develop Environment - http://wizwiki.net/wiki/ Last update: 2015/02/09 products:wiz550web:wiz550webgsg_en http://wizwiki.net/wiki/doku.php?id=products:wiz550web:wiz550webgsg_en 13:05 ● Eclipse IDE for C/C++ Developers, Kepler Service Release 2 ● ARM GCC 4.8.3 (2014q1) Product Preview Hello World Product Contents Ordering Part No: WIZ550web ● WIZ550web module x 1 Ordering Part No: WIZ550web-EVB ● WIZ550web module x 1 ● WIZ550web baseboard x 1 http://wizwiki.net/wiki/ Printed on 2015/02/09 17:48 2015/02/09 17:48 3/21 Getting Started Guide with WIZ550web ● LAN cable x 1 ● Serial cable x 1 ● 12V Power adapter x 1 SD card is option for both WIZ550web and WIZ550web-EVB Refer to recommended lists of SD card. Vendor Capacity(Bytes) Type Class 2G SD n/a Sandisk 4G SDHC 4 8G SDHC 4 Samsung 4G SDHC 6 Transcend 4G SDHC 4,10 SD card Initialization WIZ550web uses Micro SD card as a storage for web content and SD card is not included as default. -
CGI Scripts: Gateways to World-Wide Web Power
Behavior Research Methods. Instruments. & Computers 1996,28 (2), 165-169 CGI scripts: Gateways to World-Wide Web power JAMES M. KIELEY Miyazaki International CoUege, Miyazaki, Japan The power of the hypertext-based information presentation system known as the World-Wide Web can be enhanced by scripts based on the common gateway interface (CG!) protocol. CG! scripts re siding on a Webserver permit the execution of computer programs that can perform a wide variety of functions that maybe useful to psychologists. Example applications are presented here, along with ref erence information for potential script developers. The majority ofinformation that people access via the permit users to input data by clicking on checkboxes, hypertext-based information presentation system known radio buttons, menus, reset buttons, and submit buttons, as the World-Wide Web (WWW) is actually stored in the and also by typing into text fields (Lemay, 1995). form of static files-that is, text and graphics files that COl was developed by the original programmers ofthe appear a certain way when viewed from a Web browser, UNIX-based CERN and NCSA HTTP Web servers to such as Netscape or Mosaic, because ofa command lan supersede a prior scripting environment called HTBIN. guage known as HTML. HTML, by its original design, is Other Web servers that support scripting, including those a simple command set used to present multimedia infor based on other operating systems, mayor may not use mation that can be accessed asynchronously. The capa the COl protocol. Early applications of COl scripts in bilities ofHTML, and, therefore, the WWW, can be im cluded using them to serve information to a browser that proved with scripts conforming to the common gateway is in a format that is otherwise unreadable, such as an SQL interface (COl) protocol. -
EECS 122, Lecture 18
Where We Are So Far… EECS 122, Lecture 18 Today’s Topics: • Networking concepts – remote access to resources Review of Where We Are – controlled sharing Introduction to Transport Layer • multiplexing: TDM, Stat Mux UDP: The User Datagram Protocol – protocols and layering • ISO reference model, encapsulation Introduction to Reliability • service model, error detection • end-to-end argument • soft state Kevin Fall, [email protected] Where We Are So Far… Where We Are So Far… • Development of the Internet • Direct-link networks – interconnection of heterogeneous networks – signals, modulation, error detection – simple best-effort service model – best-effort delivery between attached – fully-connected graph of hosts (routing) stations – possible error correction using codes • Internet scaling issues – MAC protocols, Ethernet – use of hierarchies in routing, addresses, DNS – use of caching in DNS Where We Are So Far… What We Are Missing… • The Internet Protocol • Access to process-level information – IP service model – currently, can only send traffic from one • best-effort datagram model computer to another • error detection in header only – no way to indicate which process or service • consistent, abstract packet, addressing should receive it • routing • Reliable transport • signaling (ICMP) – no way to know whether data received was • multicasting, IGMP, multicast routing correct • IP futures with IPv6 – no way to correct for delivery errors 1 Problem Set #3 The Transport Layer • Peterson & Davie: • provide application-to-application -
Post Sockets - a Modern Systems Network API Mihail Yanev (2065983) April 23, 2018
Post Sockets - A Modern Systems Network API Mihail Yanev (2065983) April 23, 2018 ABSTRACT In addition to providing native solutions for problems, es- The Berkeley Sockets API has been the de-facto standard tablishing optimal connection with a Remote point or struc- systems API for networking. However, designed more than tured data communication, we have identified that a com- three decades ago, it is not a good match for the networking mon issue with many of the previously provided networking applications today. We have identified three different sets of solutions has been leaving the products vulnerable to code problems in the Sockets API. In this paper, we present an injections and/or buffer overflow attacks. The root cause implementation of Post Sockets - a modern API, proposed by for such problems has mostly proved to be poor memory Trammell et al. that solves the identified limitations. This or resource management. For this reason, we have decided paper can be used for basis of evaluation of the maturity of to use the Rust programming language to implement the Post Sockets and if successful to promote its introduction as new API. Rust is a programming language, that provides a replacement API to Berkeley Sockets. data integrity and memory safety guarantees. It uses region based memory, freeing the programmer from the responsibil- ity of manually managing the heap resources. This in turn 1. INTRODUCTION eliminates the possibility of leaving the code vulnerable to Over the years, writing networked applications has be- resource management errors, as this is handled by the lan- come increasingly difficult. -
Requirements
Requirements • System Requirements, page 1 • Considerations for Thin Clients, page 3 • Port Requirements, page 4 • Supported Codecs, page 5 • AnyConnect Profiles and the Cisco ASA, page 5 System Requirements Important Each of the components listed in the following table must meet the requirements. Use of unsupported components can result in a nonfunctional deployment. Component Requirements SUSE Linux thin clients—Hardware SP2-supported hardware: Dell Wyse Z50D or D50D SP3-supported hardware: Dell Wyse D50Q, Z50Q, or Z50QQ Note For information about video resolution and performance, see Video Resolution, on page 3. SUSE Linux Platform SP2 Image 11.2.092 SUSE Linux Platform SP3 Image 11.3.092 Deployment and Installation Guide for Cisco Virtualization Experience Media Engine for SUSE Linux Release 11.0 1 Requirements System Requirements Component Requirements Hosted virtual desktop OS (server-side) • Microsoft Windows 7 32 bit • Microsoft Windows 7 64 bit • Microsoft Windows 8 32 bit • Microsoft Windows 8 64 bit • Microsoft Windows 8.1 32 bit • Microsoft Windows 8.1 64 bit Connection broker for the hosted virtual desktop • Citrix XenDesktop 7.1, 7.5, or 7.6 • Citrix Xenapp 6.5, 7.5 or 7.6—Published desktops only • VMware Horizon View 5.3—Published desktops only • VMware Horizon 6.0 (with View)—Published desktops only • VMware Horizon 6 version 6.1.0—Published desktops only Receiver or client (on the thin client) The platform SP2 or SP3 image includes the required receiver or client. Cisco Unified Communications client Cisco Jabber for Windows 11.0 running on the hosted virtual desktop on the hosted virtual desktop (HVD). -
Introduction to RAW-Sockets Jens Heuschkel, Tobias Hofmann, Thorsten Hollstein, Joel Kuepper
Introduction to RAW-sockets Jens Heuschkel, Tobias Hofmann, Thorsten Hollstein, Joel Kuepper 16.05.2017 Technical Report No. TUD-CS-2017-0111 Technische Universität Darmstadt Telecooperation Report No. TR-19, The Technical Reports Series of the TK Research Division, TU Darmstadt ISSN 1864-0516 http://www.tk.informatik.tu-darmstadt.de/de/publications/ Introduction to RAW-sockets by Heuschkel, Jens Hofmann, Tobias Hollstein, Thorsten Kuepper, Joel May 17, 2017 Abstract This document is intended to give an introduction into the programming with RAW-sockets and the related PACKET-sockets. RAW-sockets are an additional type of Internet socket available in addition to the well known DATAGRAM- and STREAM-sockets. They do allow the user to see and manipulate the information used for transmitting the data instead of hiding these details, like it is the case with the usually used STREAM- or DATAGRAM sockets. To give the reader an introduction into the subject we will first give an overview about the different APIs provided by Windows, Linux and Unix (FreeBSD, Mac OS X) and additional libraries that can be used OS-independent. In the next section we show general problems that have to be addressed by the programmer when working with RAW-sockets. We will then provide an introduction into the steps necessary to use the APIs or libraries, which functionality the different concepts provide to the programmer and what they provide to simplify using RAW and PACKET-sockets. This section includes examples of how to use the different functions provided by the APIs. Finally in the additional material we will give some complete examples that show the concepts and can be used as a basis to write own programs. -
The Common Gateway Interface and Server-Side Programming
WebWeb MasterMaster 11 IFIIFI Andrea G. B. Tettamanzi Université de Nice Sophia Antipolis Département Informatique [email protected] Andrea G. B. Tettamanzi, 2019 1 Unit 3 The Common Gateway Interface and Server-side Programming Andrea G. B. Tettamanzi, 2019 2 Agenda • The Common Gateway Interface • Server-Side Programming Andrea G. B. Tettamanzi, 2019 3 Introduction • An HTTP server is often used as a gateway to a different information system (legacy or not), for example – an existing body of documents – an existing database application • The Common Gateway Interface (CGI) is an agreement between HTTP server implementors about how to integrate such gateway scripts and programs • It was typically (but not exclusively) used in conjunction with HTML forms to build database applications • Nowadays largely superseded by dynamic Web content technologies such as PHP, ASP.NET, Java Servlets, and Node.js Andrea G. B. Tettamanzi, 2019 4 The Common Gateway Interface • The Common Gateway Interface (CGI) is a de facto standard protocol for Web servers to execute an external program that generates a Web page dynamically • The external program executes like a console application running on the same machine as the Web server (the host) • Such program is known as a CGI script or simply as a CGI Andrea G. B. Tettamanzi, 2019 5 How Does That Work? • Each time a client requests the URL corresponding to a CGI program, the server will execute it in real-time – E.g.: GET http://www.example.org/cgi-bin/add?x=2&y=2 • The output of the program will go more or less directly to the client • Strictly speaking, the “input” to the program is the HTTP request • Environment variables are used to pass data about the request from the server to the program – They are accessed by the script in a system-defined manner – Missing environment variable = NULL value – Character encoding is system-defined Andrea G.