Explain Telnet Protocol in Hindi
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Network Printing Guide
Network Printing Guide Windows 95/98/Me Configuration Windows 2000 Configuration Windows XP Configuration Windows NT 4.0 Configuration NetWare Configuration Macintosh Configuration Appendix For safe and correct use of this machine, please be sure to read the Safety Information in the Operating Instructions that comes with the machine before you use it. Introduction To get maximum versatility from this machine all operators should carefully read and follow the instruc- tions in this manual. Please keep this manual in a handy place near the machine. Important Contents of this manual are subject to change without prior notice. In no event will the company be li- able for direct, indirect, special, incidental, or consequential damages as a result of handling or oper- ating the machine. Software Version Conventions Used in this Manual • NetWare 3.x means NetWare 3.12 and 3.2. • NetWare 4.x means NetWare 4.1, 4.11 and IntranetWare. Trademarks Apple, AppleTalk, EtherTalk, LaserWriter, Macintosh and Mac are registered trademarks of Apple Computer, Inc. Ethernet is a registered trademark of Xerox Corporation. Microsoft, Windows and Windows NT are registered trademarks of Microsoft Corporation in the United States and/or other countries. Netscape and Netscape Navigator are registered trademarks of Netscape Communications Corpora- tion. Novell, NetWare and NDS are registered trademarks of Novell, Inc. PostScript is a registered trademark of Adobe Systems, Incorporated. Sun is a registered trademark of Sun Microsystems, Inc. SunOS is a trademark of Sun Microsystems, Inc. Other product names used herein are for identification purposes only and might be trademarks of their respective companies. -
Ipsec, SSL, Firewall, Wireless Security
IPSec 1 Outline • Internet Protocol – IPv6 • IPSec – Security Association (SA) – IPSec Base Protocol (AH, ESP) – Encapsulation Mode (transport, tunnel) 2 IPv6 Header • Initial motivation: – 32-bit address space soon to be completely allocated. – Expands addresses to 128 bits • 430,000,000,000,000,000,000 for every square inch of earth’s surface! • Solves IPv4 problem of insufficient address space • Additional motivation: – header format helps speedy processing/forwarding – header changes to facilitate QoS IPv6 datagram format: – fixed-length 40 byte header – no fragmentation allowed 3 IPv6 Header (Cont) Priority: identify priority among datagrams in flow Flow Label: identify datagrams in same “flow.” (concept of“flow” not well defined). Next header: identify upper layer protocol for data 4 Other Changes from IPv4 • Checksum: removed entirely to reduce processing time at each hop • Options: allowed, but outside of header, indicated by “Next Header” field • ICMPv6: new version of ICMP – additional message types, e.g. “Packet Too Big” – multicast group management functions 5 IPv6 Security – IPsec mandated • IPsec is mandated in IPv6 – This means that all implementations (i.e. hosts, routers, etc) must have IPsec capability to be considered as IPv6-conformant • When (If?) IPv6 is in widespread use, this means that IPsec will be installed everywhere – At the moment, IPsec is more common in network devices (routers, etc) than user hosts, but this would change with IPsec • All hosts having IPsec => real end-to-end security possible 6 IPv6 Security • Enough IP addrs for every imaginable device + Real end-to-end security = Ability to securely communicate from anything to anything 7 IPv6 Security – harder to scan networks • With IPv4, it is easy to scan a network – With tools like nmap, can scan a typical subnet in a few minutes see: http://www.insecure.org/nmap/ – Returning list of active hosts and open ports – Many worms also operate by scanning • e.g. -
Solutions to Chapter 2
CS413 Computer Networks ASN 4 Solutions Solutions to Assignment #4 3. What difference does it make to the network layer if the underlying data link layer provides a connection-oriented service versus a connectionless service? [4 marks] Solution: If the data link layer provides a connection-oriented service to the network layer, then the network layer must precede all transfer of information with a connection setup procedure (2). If the connection-oriented service includes assurances that frames of information are transferred correctly and in sequence by the data link layer, the network layer can then assume that the packets it sends to its neighbor traverse an error-free pipe. On the other hand, if the data link layer is connectionless, then each frame is sent independently through the data link, probably in unconfirmed manner (without acknowledgments or retransmissions). In this case the network layer cannot make assumptions about the sequencing or correctness of the packets it exchanges with its neighbors (2). The Ethernet local area network provides an example of connectionless transfer of data link frames. The transfer of frames using "Type 2" service in Logical Link Control (discussed in Chapter 6) provides a connection-oriented data link control example. 4. Suppose transmission channels become virtually error-free. Is the data link layer still needed? [2 marks – 1 for the answer and 1 for explanation] Solution: The data link layer is still needed(1) for framing the data and for flow control over the transmission channel. In a multiple access medium such as a LAN, the data link layer is required to coordinate access to the shared medium among the multiple users (1). -
SILC-A SECURED INTERNET CHAT PROTOCOL Anindita Sinha1, Saugata Sinha2 Asst
ISSN (Print) : 2320 – 3765 ISSN (Online): 2278 – 8875 International Journal of Advanced Research in Electrical, Electronics and Instrumentation Engineering Vol. 2, Issue 5, May 2013 SILC-A SECURED INTERNET CHAT PROTOCOL Anindita Sinha1, Saugata Sinha2 Asst. Prof, Dept. of ECE, Siliguri Institute of Technology, Sukna, Siliguri, West Bengal, India 1 Network Engineer, Network Dept, Ericsson Global India Ltd, India2 Abstract:-. The Secure Internet Live Conferencing (SILC) protocol, a new generation chat protocol provides full featured conferencing services, compared to any other chat protocol. Its main interesting point is security which has been described all through the paper. We have studied how encryption and authentication of the messages in the network achieves security. The security has been the primary goal of the SILC protocol and the protocol has been designed from the day one security in mind. In this paper we have studied about different keys which have been used to achieve security in the SILC protocol. The main function of SILC is to achieve SECURITY which is most important in any chat protocol. We also have studied different command for communication in chat protocols. Keywords: SILC protocol, IM, MIME, security I.INTRODUCTION SILC stands for “SECURE INTERNET LIVE CONFERENCING”. SILC is a secure communication platform, looks similar to IRC, first protocol & quickly gained the status of being the most popular chat on the net. The security is important feature in applications & protocols in contemporary network environment. It is not anymore enough to just provide services; they need to be secure services. The SILC protocol is a new generation chat protocol which provides full featured conferencing services; additionally it provides security by encrypting & authenticating the messages in the network. -
Secure Shell Encrypt and Authenticate Remote Connections to Secure Applications and Data Across Open Networks
Product overview OpenText Secure Shell Encrypt and authenticate remote connections to secure applications and data across open networks Comprehensive Data security is an ongoing concern for organizations. Sensitive, security across proprietary information must always be protected—at rest and networks in motion. The challenge for organizations that provide access to applications and data on host systems is keeping the data Support for Secure Shell (SSH) secure while enabling access from remote computers and devices, whether in a local or wide-area network. ™ Strong SSL/TLS OpenText Secure Shell is a comprehensive security solution that safeguards network ® encryption traffic, including internet communication, between host systems (mainframes, UNIX ™ servers and X Window System applications) and remote PCs and web browsers. When ™ ™ ™ ™ Powerful Kerberos included with OpenText Exceed or OpenText HostExplorer , it provides Secure Shell 2 (SSH-2), Secure Sockets Layer (SSL), LIPKEY and Kerberos security mechanisms to ensure authentication security for communication types, such as X11, NFS, terminal emulation (Telnet), FTP support and any TCP/IP protocol. Secure Shell encrypts data to meet the toughest standards and requirements, such as FIPS 140-2. ™ Secure Shell is an add-on product in the OpenText Connectivity suite, which encrypts application traffic across networks. It helps organizations achieve security compliance by providing Secure Shell (SSH) capabilities. Moreover, seamless integration with other products in the Connectivity suite means zero disruption to the users who remotely access data and applications from web browsers and desktop computers. Secure Shell provides support for the following standards-based security protocols: Secure Shell (SSH)—A transport protocol that allows users to log on to other computers over a network, execute commands on remote machines and securely move files from one machine to another. -
Arc Hydro Geoprocessing Tools - Tutorial
Arc Hydro Geoprocessing Tools - Tutorial Version 2.0 – October 2011 ESRI 380 New York St., Redlands, CA 92373-8100, USA TEL 909-793-2853 FAX 909-793-5953 E-MAIL [email protected] WEB www.esri.com Arc Hydro GP Tools v 2.0 – Tutorial Copyright © 2011 Esri All rights reserved. Printed in the United States of America. The information contained in this document is the exclusive property of Esri. This work is protected under United States copyright law and other international copyright treaties and conventions. No part of this work may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or by any information storage or retrieval system, except as expressly permitted in writing by Esri. All requests should be sent to Attention: Contracts Manager, Esri, 380 New York Street, Redlands, CA 92373-8100, USA. The information contained in this document is subject to change without notice. October 2011 i Arc Hydro GP Tools v 2.0 – Tutorial Table of Contents Introduction 5 Objective 5 Loading Arc Hydro Tools Toolbox 5 Accessing the Arc Hydro Geoprocessing Tools Help 7 Arc Hydro Tools Configuration 9 Arc Hydro Setup 10 1. Set Target Locations 10 2. Set Batch Target Locations 13 3. Standard Geoprocessing Configuration 15 Terrain Preprocessing 16 1. Level DEM 17 2. DEM Reconditioning 22 3. Assign Stream Slope 25 4. Burn Stream Slope 27 5. Build Walls 28 6. Sink Prescreening 29 7. Sink Evaluation 29 8. Sink Selection 31 9. Fill Sinks 32 10. Flow Direction 33 11. -
Secure Telnet
The following paper was originally published in the Proceedings of the Fifth USENIX UNIX Security Symposium Salt Lake City, Utah, June 1995. STEL: Secure TELnet David Vincenzetti, Stefano Taino, and Fabio Bolognesi Computer Emergency Resource Team Italy Department of Computer Science University of Milan, Italy For more information about USENIX Association contact: 1. Phone: 510 528-8649 2. FAX: 510 548-5738 3. Email: [email protected] 4. WWW URL: http://www.usenix.org STEL Secure TELnet David Vincenzetti Stefano Taino Fabio Bolognesi fvince k taino k b ologdsiunimiit CERTIT Computer Emergency Response Team ITaly Department of Computer Science University of Milan ITALY June Abstract Eavesdropping is b ecoming rampant on the Internet We as CERTIT have recorded a great numb er of sning attacks in the Italian community In fact sning is the most p opular hackers attack technique all over the Internet This pap er presents a secure telnet implementation whichhas b een designed by the Italian CERT to makeeavesdropping ineective to remote terminal sessions It is not to b e considered as a denitive solution but rather as a bandaid solution to deal with one of the most serious security threats of the moment Intro duction STEL stands for Secure TELnet We started developing STEL at the University of Milan when we realized that eavesdropping was a very serious problem and we did not like the freeware solutions that were available at that time It was ab out three years ago Still as far as we know e tapping problem and there are no really satisfying -
Telnet Client 5.11 Ssh Support
TELNET CLIENT 5.11 SSH SUPPORT This document provides This document describes how to install and configure SSH support in Wavelink Telnet Client 5.11. information on the SSH support available in Telnet Client 5.11 OVERVIEW OF SSH SUPPORT Secure Shell (SSH) is a protocol developed for transmitting private information over the Internet. SSH OVERVIEW encrypts data that is transferred over the Telnet session. • Overview of SSH The Telnet Client supports SSH version 1 and 2 and will automatically select the most secure protocol Support that the SSH server supports. • Installing Windows SSH Support This document describes the following: • Configuring the host • Installing Windows SSH support utility profile for SSH • Configuring the host profile for SSH support support • Deploying Windows • Deploying Windows SSH support to the device through Avalanche or ActiveSync SSH Support • Revision History INSTALLING WINDOWS SSH SUPPORT Installing SSH support is a two-step process. First, install SSH support on the PC from which you will deploy Telnet. Once you install SSH support on the PC, use Avalanche or ActiveSync to deploy the utility to the device. To install SSH support on your PC: 1. Obtain the installation executable for SSH support. NOTE: To obtain the Wavelink SSH support utility install, go to http://www.wavelink.com/downloads/ files/sshagreement.aspx. 2. Install SSH support on the PC from which you will deploy the Telnet Client. CONFIGURING THE HOST PROFILE FOR SSH SUPPORT SSH support is configured from the Host Profiles window of the configuration utility. NOTE: SSH is only an active option if SSH support has been installed on the PC running the Telnet Client configuration utility. -
Cheat Sheet – Common Ports (PDF)
COMMON PORTS packetlife.net TCP/UDP Port Numbers 7 Echo 554 RTSP 2745 Bagle.H 6891-6901 Windows Live 19 Chargen 546-547 DHCPv6 2967 Symantec AV 6970 Quicktime 20-21 FTP 560 rmonitor 3050 Interbase DB 7212 GhostSurf 22 SSH/SCP 563 NNTP over SSL 3074 XBOX Live 7648-7649 CU-SeeMe 23 Telnet 587 SMTP 3124 HTTP Proxy 8000 Internet Radio 25 SMTP 591 FileMaker 3127 MyDoom 8080 HTTP Proxy 42 WINS Replication 593 Microsoft DCOM 3128 HTTP Proxy 8086-8087 Kaspersky AV 43 WHOIS 631 Internet Printing 3222 GLBP 8118 Privoxy 49 TACACS 636 LDAP over SSL 3260 iSCSI Target 8200 VMware Server 53 DNS 639 MSDP (PIM) 3306 MySQL 8500 Adobe ColdFusion 67-68 DHCP/BOOTP 646 LDP (MPLS) 3389 Terminal Server 8767 TeamSpeak 69 TFTP 691 MS Exchange 3689 iTunes 8866 Bagle.B 70 Gopher 860 iSCSI 3690 Subversion 9100 HP JetDirect 79 Finger 873 rsync 3724 World of Warcraft 9101-9103 Bacula 80 HTTP 902 VMware Server 3784-3785 Ventrilo 9119 MXit 88 Kerberos 989-990 FTP over SSL 4333 mSQL 9800 WebDAV 102 MS Exchange 993 IMAP4 over SSL 4444 Blaster 9898 Dabber 110 POP3 995 POP3 over SSL 4664 Google Desktop 9988 Rbot/Spybot 113 Ident 1025 Microsoft RPC 4672 eMule 9999 Urchin 119 NNTP (Usenet) 1026-1029 Windows Messenger 4899 Radmin 10000 Webmin 123 NTP 1080 SOCKS Proxy 5000 UPnP 10000 BackupExec 135 Microsoft RPC 1080 MyDoom 5001 Slingbox 10113-10116 NetIQ 137-139 NetBIOS 1194 OpenVPN 5001 iperf 11371 OpenPGP 143 IMAP4 1214 Kazaa 5004-5005 RTP 12035-12036 Second Life 161-162 SNMP 1241 Nessus 5050 Yahoo! Messenger 12345 NetBus 177 XDMCP 1311 Dell OpenManage 5060 SIP 13720-13721 -
TCP/IP Standard Applications Telnet - SSH - FTP - SMTP - HTTP
TCP/IP Standard Applications Telnet - SSH - FTP - SMTP - HTTP Virtual Terminal, Secure Shell, File Transfer, Email, WWW Agenda • Telnet (Virtual Terminal) • SSH • FTP (File Transfer) • E-Mail and SMTP • WWW and HTTP © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 2 What is Telnet? • Telnet is a standard method to communicate with another Internet host • Telnet provides a standard interface for terminal devices and terminal-oriented processes through a network • using the Telnet protocol user on a local host can remote-login and execute commands on another distant host • Telnet employs a client-server model – a Telnet client "looks and feels" like a Terminal on a distant server – even today Telnet provides a text-based user interface © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 3 Local and Remote Terminals network local terminal workstation Host as remote terminal with Telnet Server with Telnet Client traditional configuration today's demand: remote login © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 4 About Telnet • Telnet was one of the first Internet applications – since the earliest demand was to connect terminals to hosts across networks • Telnet is one of the most popular Internet applications because – of its flexibility (checking E-Mails, etc.) – it does not waste much network resources – because Telnet clients are integrated in every UNIX environment (and other operating systems) © 2016, D.I. Lindner / D.I. Haas Telnet-SSH-FTP-SMTP-HTTP, v6.0 5 Telnet Basics • Telnet is connection oriented and uses the TCP protocol • clients connect to the "well-known" destination port 23 on the server side • protocol specification: RFC 854 • three main ideas: – concept of Network Virtual Terminals (NVTs) – principle of negotiated options – a symmetric view of terminals and (server-) processes © 2016, D.I. -
OSI Model and Network Protocols
CHAPTER4 FOUR OSI Model and Network Protocols Objectives 1.1 Explain the function of common networking protocols . TCP . FTP . UDP . TCP/IP suite . DHCP . TFTP . DNS . HTTP(S) . ARP . SIP (VoIP) . RTP (VoIP) . SSH . POP3 . NTP . IMAP4 . Telnet . SMTP . SNMP2/3 . ICMP . IGMP . TLS 134 Chapter 4: OSI Model and Network Protocols 4.1 Explain the function of each layer of the OSI model . Layer 1 – physical . Layer 2 – data link . Layer 3 – network . Layer 4 – transport . Layer 5 – session . Layer 6 – presentation . Layer 7 – application What You Need To Know . Identify the seven layers of the OSI model. Identify the function of each layer of the OSI model. Identify the layer at which networking devices function. Identify the function of various networking protocols. Introduction One of the most important networking concepts to understand is the Open Systems Interconnect (OSI) reference model. This conceptual model, created by the International Organization for Standardization (ISO) in 1978 and revised in 1984, describes a network architecture that allows data to be passed between computer systems. This chapter looks at the OSI model and describes how it relates to real-world networking. It also examines how common network devices relate to the OSI model. Even though the OSI model is conceptual, an appreciation of its purpose and function can help you better understand how protocol suites and network architectures work in practical applications. The OSI Seven-Layer Model As shown in Figure 4.1, the OSI reference model is built, bottom to top, in the following order: physical, data link, network, transport, session, presentation, and application. -
Medium Access Control Layer
Telematics Chapter 5: Medium Access Control Sublayer User Server watching with video Beispielbildvideo clip clips Application Layer Application Layer Presentation Layer Presentation Layer Session Layer Session Layer Transport Layer Transport Layer Network Layer Network Layer Network Layer Univ.-Prof. Dr.-Ing. Jochen H. Schiller Data Link Layer Data Link Layer Data Link Layer Computer Systems and Telematics (CST) Physical Layer Physical Layer Physical Layer Institute of Computer Science Freie Universität Berlin http://cst.mi.fu-berlin.de Contents ● Design Issues ● Metropolitan Area Networks ● Network Topologies (MAN) ● The Channel Allocation Problem ● Wide Area Networks (WAN) ● Multiple Access Protocols ● Frame Relay (historical) ● Ethernet ● ATM ● IEEE 802.2 – Logical Link Control ● SDH ● Token Bus (historical) ● Network Infrastructure ● Token Ring (historical) ● Virtual LANs ● Fiber Distributed Data Interface ● Structured Cabling Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.2 Design Issues Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.3 Design Issues ● Two kinds of connections in networks ● Point-to-point connections OSI Reference Model ● Broadcast (Multi-access channel, Application Layer Random access channel) Presentation Layer ● In a network with broadcast Session Layer connections ● Who gets the channel? Transport Layer Network Layer ● Protocols used to determine who gets next access to the channel Data Link Layer ● Medium Access Control (MAC) sublayer Physical Layer Univ.-Prof. Dr.-Ing. Jochen H. Schiller ▪ cst.mi.fu-berlin.de ▪ Telematics ▪ Chapter 5: Medium Access Control Sublayer 5.4 Network Types for the Local Range ● LLC layer: uniform interface and same frame format to upper layers ● MAC layer: defines medium access ..