© 2002, Cisco Systems, Inc. All rights reserved. © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-2© 2002, Cisco Systems, Inc. All rights reserved. 2 Configuring Serial Point-to-Point Encapsulation © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-3 Objectives Upon completing this lesson, you will be able to: • Use Cisco IOS commands to configure serial interfaces using HDLC and PPP encapsulation for leased-line connections, given a functioning router • Use show commands to identify anomalies in HDLC and PPP encapsulation for leased-line connections, given an operational router • Use debug commands to identify events and anomalies in PPP configuration for leased-line connections, given an operational router © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-4 • Supports only single-protocol environments HDLC Frame Format • Uses a proprietary data field to support multiprotocol environments © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-5 Router(config-if)#encapsulation hdlc • Enables HDLC encapsulation • Uses the default encapsulation on synchronous serial interfaces Configuring HDLC Encapsulation © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-6 • PPP can carry packets from several protocol suites using NCP. • PPP controls the setup of several link options using LCP. An Overview of PPP © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-7 Layering PPP Elements • PPP: A data link with network layer services © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-8 PPP LCP Configuration Options © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-9 PPP Session Establishment • Two PPP authentication protocols: PAP and CHAP © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0—7-10 • Passwords sent in clear text • Peer in control of attempts PPP Authentication Protocols [...]... external server is in control of attempts © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 1 Configuring PPP and Authentication Overview © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 2 Configuring PPP Router(config-if) #encapsulation ppp • Enables PPP encapsulation © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 3 Configuring PPP Authentication Router(config)#hostname... © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 4 Configuring PPP Authentication (Cont.) Router(config-if)#ppp authentication {chap | chap pap | pap chap | pap} • Enables PAP and/or CHAP authentication © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 5 CHAP Configuration Example © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 6 Verifying the HDLC and PPP Encapsulation. .. © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 7 Verifying PPP Authentication • debug ppp authentication shows successful CHAP output © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 8 Summary • HDLC is the Cisco default data-link layer protocol for encapsulating data on synchronous serial data links • PPP encapsulates network layer protocol information over point-to-point links... layer protocol © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-1 9 Summary (Cont.) • When configuring PPP authentication, you can select PAP or CHAP In general, CHAP is the preferred protocol • You enable PPP with the encapsulation ppp command and PPP authentication with the ppp authentication command • Use the show interface command to verify proper configuration of PPP encapsulation • The... Use the show interface command to verify proper configuration of PPP encapsulation • The debug ppp authentication command displays the authentication exchange sequence © 2002, Cisco Systems, Inc All rights reserved ICND v2.0— 7-2 0 ... Systems, Inc All rights reserved ICND v2.0— 7-1 6 Verifying the HDLC and PPP Encapsulation Configuration Router#show interface s0 Serial0 is up, line protocol is up Hardware is HD64570 Internet address is 10.140.1.2/24 MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec, rely 255/255, load 1/255 Encapsulation PPP, loopback not set, keepalive set (10 sec) LCP Open Open: IPCP, CDPCP Last input 00:00:05, output 00:00:05, . All rights reserved. 2 Configuring Serial Point-to-Point Encapsulation © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0— 7-3 Objectives Upon completing. v2.0— 7-1 3 Router(config-if) #encapsulation ppp • Enables PPP encapsulation Configuring PPP © 2002, Cisco Systems, Inc. All rights reserved. ICND v2.0— 7-1 4 Router(config)#hostname