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CPET/ECET 355. 12. Point-to-Point Access: PPP Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne www.ecet.ipfw.edu/~lin. Point-to-Point Access: PPP. Data Link Protocol for
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CPET/ECET 355 12. Point-to-Point Access: PPP Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne www.ecet.ipfw.edu/~lin 11. Data Link Control and Protocols - Lin
Point-to-Point Access: PPP • Data Link Protocol for • Dial-up modems • DSL modems • Cable modems • PPP Defines • Frame format • Negotiate and establish exchange of data • Encapsulation of network layer data • Authentication 11. Data Link Control and Protocols - Lin
PPP – Frame Format • Address Field • Control Field • Protocol Field • Data Field • Frame Check Sequence (FCS) From p. 296, Figure 12.1 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP – Transition States • Idle, Establishing, Authenticating, Networking, Terminating From p. 296, Figure 12.2 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP – Stack • Three Protocols • Link Control protocol • Authentication protocol, and • Network Control protocol From p. 297, Figure 12.3 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP – Link Control Protocol • LCP Responsibilities • Establishing, Maintaining, Configuring, and Terminating Links • Payload: Code, ID, Length, Information Fields From p. 298, Figure 12.4 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP – LCP Packets From p. 298, Table 12.1 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP – LCP Packets • Configuration Packets • Configuration-request • Configuration-ack • Configuration-nak • Configuration-reject • Link Termination Packets • Termination-request • Termination-ack 11. Data Link Control and Protocols - Lin
PPP – LCP Packets • Link Monitoring and Debugging Packets • Code-reject • Protocol-reject • Echo-request • Echo-reply • Discard-request • Options (in the info field) 11. Data Link Control and Protocols - Lin
LCP Packet Option From p. 298, Figure 12.4 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
Authentication Protocols • Password Authentication Protocols (PAP) • User sends ID (user name), and Password • System checks the validity: accept, or reject • Challenge Handshake Authentication Protocols (CHAP) • System send a challenge packet • The user applies a predefined function, and reply the challenge packet • The system does the same to see if the same result can be obtained: accept or reject 11. Data Link Control and Protocols - Lin
PAP (Password Authentication) From p. 300, Figure 12.5 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PAP Packets From p. 301, Figure 12.6 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
CHAP From p. 302, Figure 12.7 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
CHAP Packets From p. 302, Figure 12.8 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
Network Control Protocol (NCP) IPCP: Internetwork Protocol Control Protocol From p. 303, Figure 12.9 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
Code Values for IPCP Packets From p. 303, Table 12.3 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
PPP Connection Example From p. 303, Figure 12.9 of Data Communications and Networking, Forouzan, McGrawHill 11. Data Link Control and Protocols - Lin
Summary Questions? 11. Data Link Control and Protocols - Lin