© 1999, cisco systems, inc. 12-1 第十二章建立串行的点对点连接

© 1999, Cisco Systems, Inc. 12-1

第十二章建立串行的点对点连接

© 1999, Cisco Systems, Inc. www.cisco.com ICND—12-2

通过本章的学习，您应该掌握以下内容：•在广域网的串行口上配置 HDLC 和 PPP 协

议•在一个 PPP 连接内配置 PAP 和 CHAP 验

证•查看点到点的 HDLC 和 PPP 协议配置情况

本章目标


WAN 概述WAN 概述

Service Provider

• 广域网连接的场所• 根据用户不同的需求提供不同的连接方案


专线同步串口

Telephone

Company电路交换

异步串口

Service

Provider包交换

同步串口

广域网连接类型 : 物理层广域网连接类型 : 物理层


Point-to-point orcircuit-switched

connection

CO Switch

Customer Premises Equipment

Demarcation

Local Loop

WAN service provider toll network

Trunks and switches

广域网的服务提供

服务商给用户分配线路的参数

S S

S SS

S S


Router connections

Network connections at the CSU/DSUEIA/TIA-232 EIA/TIA-449 EIA-530V.35 X.21

CSU/DSU

End user device

Service Provider

DTE

DCE

PPP 的串口连接PPP 的串口连接


专线

包交换

PPP, SLIP, HDLC

HDLC, PPP, SLIP

电路交换

X.25, Frame Relay, ATM

广域网连接类型 : 数据链路层广域网连接类型 : 数据链路层

Telephone

Company

Service

Provider


Flag Address Control Data FCS Flag

HDLC

• 支持单一的协议环境

Flag Address Control Proprietary Data FCS Flag

Cisco HDLC

HDLC 帧格式

• Cisco 的 HDLC 具有 proprietary 字节提供对多协议环境的支持


HDLC 命令

Router(config-if)#encapsulation hdlc

• 启用 HDLC 封装• HDLC 是同步串口的缺省封装格式


PPP EncapsulationTCP/IPNovell IPXAppleTalk

Multiple protocol encapsulations using

NCPs in PPP

•PPP 可以通过 NCP 携带多个协议的数据包•PPP 可以通过 LCP 建立和控制连接

Link setup and control using LCP in PPP

PPP 综述


Synchronous or AsynchronousPhysical Media

Link Control Protocol

Authentication, other options

Network Control Protocol PPP

Data LinkLayer

PhysicalLayer

NetworkLayer

IPCP IPXCP Many Others

IP IPX Layer 3 Protocols

PPP 分层结构

PPP—A data link with network-layer services


Feature How It Operates Protocol

Authentication PAP

CHAPPerform Challenge Handshake

Require a password

CompressionCompress data at source; reproduce data at destination

Stacker orPredictor

Error Detection

Avoid frame looping

Monitor data dropped on link Magic Number

Multilink Load balancing across multiple links

Multilink Protocol (MP)

PPP LCP 配置选项


PPP 验证概述

两种 PPP 验证协议 : PAP 和 CHAP

PPP 会话的建立1 链路建立2 验证阶段

3 网路层协议连接

Dialup or Circuit-Switched

Network


• 密码明文传输• 验证两端是同等的

选择 PPP 验证协议

Remote Router(SantaCruz)

Central-Site Router (HQ)

Hostname: santacruzPassword: boardwalk

username santacruzpassword boardwalk

PAP 2-Way Handshake

“ santacruz, boardwalk”“ santacruz, boardwalk”

Accept/RejectAccept/Reject


选择 PPP 验证协议

Remote Router(SantaCruz)

Central-Site Router (HQ)

Hostname: santacruzPassword: boardwalk

username santacruzpassword boardwalk

CHAP3-Way Handshake

ChallengeChallenge

ResponseResponse

Accept/RejectAccept/Reject

密码是加密的


配置 PPP 验证总述

ServiceProvider

Verify who you are.

Router to Be Authenticated(The router that initiated the call.)

ppp encapsulation

hostname username / password ppp authentication

Authenticating Router(The router that received the call.)

ppp encapsulation

hostname username / password ppp authentication

Enabling PPP

Enabling PPP Authentication

Enabling PPP

Enabling PPP Authentication


配置 PPP

Router(config-if)#encapsulation ppp

激活 PPP 验证


配置 PPP 验证

Router(config)#hostname name

• 给路由器命名

Router(config)#username name password password

• 提供需要验证的路由器的名称和密码


配置 PPP 验证

Router(config-if)#ppp authentication{chap | chap pap | pap chap | pap}

激活 PAP 或 CHAP 验证


CHAP 配置举例

hostname leftusername right password sameone!int serial 0

ip address 10.0.1.1 255.255.255.0 encapsulation ppp ppp authentication CHAP

hostname leftusername right password sameone!int serial 0

ip address 10.0.1.1 255.255.255.0 encapsulation ppp ppp authentication CHAP

hostname right

username left password sameone

!

int serial 0

ip address 10.0.1.2 255.255.255.0

encapsulation ppp

ppp authentication CHAP

hostname right

username left password sameone

!

int serial 0

ip address 10.0.1.2 255.255.255.0

encapsulation ppp

ppp authentication CHAP

Leftrouter

Rightrouter

PSTN/ISDN


查看 HDLC 和 PPP 的封装Router#show interface s0Serial0 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, output hang never Last clearing of "show interface" counters never Queueing strategy: fifo Output queue 0/40, 0 drops; input queue 0/75, 0 drops 5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 38021 packets input, 5656110 bytes, 0 no buffer Received 23488 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort 38097 packets output, 2135697 bytes, 0 underruns 0 output errors, 0 collisions, 6045 interface resets 0 output buffer failures, 0 output buffers swapped out 482 carrier transitions DCD=up DSR=up DTR=up RTS=up CTS=up


利用 debug ppp authentication 命令查看 PPP 验证

4d20h: %LINK-3-UPDOWN: Interface Serial0, changed state to up4d20h: Se0 PPP: Treating connection as a dedicated line4d20h: Se0 PPP: Phase is AUTHENTICATING, by both4d20h: Se0 CHAP: O CHALLENGE id 2 len 28 from ”left"4d20h: Se0 CHAP: I CHALLENGE id 3 len 28 from ”right"4d20h: Se0 CHAP: O RESPONSE id 3 len 28 from ”left"4d20h: Se0 CHAP: I RESPONSE id 2 len 28 from ”right"4d20h: Se0 CHAP: O SUCCESS id 2 len 44d20h: Se0 CHAP: I SUCCESS id 3 len 44d20h: dialer Protocol up for Se04d20h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up

4d20h: %LINK-3-UPDOWN: Interface Serial0, changed state to up4d20h: Se0 PPP: Treating connection as a dedicated line4d20h: Se0 PPP: Phase is AUTHENTICATING, by both4d20h: Se0 CHAP: O CHALLENGE id 2 len 28 from ”left"4d20h: Se0 CHAP: I CHALLENGE id 3 len 28 from ”right"4d20h: Se0 CHAP: O RESPONSE id 3 len 28 from ”left"4d20h: Se0 CHAP: I RESPONSE id 2 len 28 from ”right"4d20h: Se0 CHAP: O SUCCESS id 2 len 44d20h: Se0 CHAP: I SUCCESS id 3 len 44d20h: dialer Protocol up for Se04d20h: %LINEPROTO-5-UPDOWN: Line protocol on Interface Serial0, changed state to up

Leftrouter

Rightrouter

Service Provider


可视化目标可视化目标pod ro’s s0A 10.140.1.2B 10.140.2.2C 10.140.3.2D 10.140.4.2E 10.140.5.2F 10.140.6.2G 10.140.7.2H 10.140.8.2I 10.140.9.2J 10.140.10.2K 10.140.11.2L 10.140.12.2

s1/0 - s2/310.140.1.1 … 10.140.12.1

core_ server10.1.1.1

wg_sw_a10.2.2.11

wg_sw_l10.13.13.11

wg_pc_a10.2.2.12

wg_pc_l10.13.13.12

wg_ro_ae0/1 e0/2

e0/2e0/1

e0

e0

fa0/23

core_sw_a10.1.1.2

wg_ro_l

core_ro10.1.1.3

fa0/24 fa0/0

LL

s0 10.140.1.2

...

10.13.13.3 s0

10.140.12.2

PPP with CHAP

PPP with CHAP

10.2.2.3


完成本章的学习后，你应该能够掌握：• 在广域网的串行口上配置 HDLC 和 PPP

协议• 在一个 PPP 连接内配置 PAP 和 CHAP

验证• 查看点到点的 HDLC 和 PPP 协议配置

情况

本章总结


1. 在 Cisco 路由器上有哪三中广域网连接类型 ?

2. PPP 有哪两种封装协议，它们有哪些优、缺点 ?

3. PPP LCP 有哪些选项 ?

问题回顾

© 1999, cisco systems, inc. 12-1 第十二章 建立串行的点对点连接

Documents

© 1999, cisco systems, inc. 12-1 第十二章建立串行的点对点连接