ISDN BRI PVDM Dialer
对于拨号一直想研究,后来还买了PVDM2-12DM和VIC2-2BRI-NT/TE,又申请了一条2B+D的ISDN线路,还有一个isdn modem。准备在29上测试,后来一直有事耽误到现在。最近同事正好做拨号的测试,可用到我之前的环境(测试时29换成39了),所幸就测试了下如何用BRI替代之前讨论过的E1来为用户提供拨号环境。关于VIC2-2BRI-NT/TE这块卡的data sheet,可以看下面的链接:
Understanding ISDN BRI Voice Interface Cards
关于ISDN的拨号方式,可以参考下面的图例,网上找的,感觉不错:
测试Topology
PC(modem)—–RJ11—–PSTN—–ISDN—2B+D—-(RJ11)ISDN Modem—RJ45—(VIC2)3925
3925配置如下
注:大部分配置跟PRI一样,没有太大区别,所以只接受部分命令
hostname Router
!
boot-start-marker
boot system flash0:c3900-universalk9-mz.SPA.151-4.M3.bin
boot-end-marker
!
aaa new-model
aaa authentication ppp default local
!
modem country v12 china
!
isdn switch-type basic-net3
!—这是isdn switch的类型,Pri是“primary-net5”
!
modemcap entry test_a:MSC=&f&d3+ms=xxxxxxxx
!—这是AT命令,在line中,用”modem autoconfig type test_a”调用
!
license udi pid C3900-SPE100/K9 sn xxxxxxx
license boot module c3900 technology-package securityk9
license boot module c3900 technology-package uck9
license boot module c3900 technology-package datak9
!—在39上,要装license才能配置这块2B+D的卡
hw-module pvdm 0/0
!—这是PVDM数字猫
!
username cisco password 0 cisco
!
interface Loopback0
ip address 33.33.33.1 255.255.255.0
!
interface BRI0/1/0
no ip address
isdn switch-type basic-net3
isdn point-to-point-setup
!—这个配置是自动加上的
isdn incoming-voice modem
!—使进来的语音路由到modem上,这里modem是PVDM
!
interface BRI0/1/1
no ip address
shutdown
isdn switch-type basic-net3
isdn point-to-point-setup
isdn incoming-voice modem
!
interface Group-Async1
ip unnumbered Loopback0
encapsulation ppp
load-interval 30
dialer in-band
dialer-group 5
peer default ip address pool DIALADDR
async mode dedicated
no keepalive
ppp authentication pap ms-chap chap
group-range 0/387 0/422
!
ip local pool DIALADDR 33.33.33.2 33.33.33.100
dialer-list 5 protocol ip permit
!
line 0/387 0/422
modem InOut
transport input all
autoselect during-login
autoselect ppp
简单分析拨号过程
1. 当PC拨号后,通过内置Modem把数字信号调制成模拟信号传出去。
2. 到达ISP后,会先进入PSTN,然后把模拟信号从PSTN转向ISDN,并传给ISDN Modem上。
3. 到达ISDN Modem后,会有两种处理方式:当接非ISDN设备时,Modem应该把模拟信号调制成数字信号传给该设备;而当接ISDN设备时,应该不做调制直接传给ISDN设备。在本测试中,VIC2就是ISDN设备,所以到达VIC2时仍然是模拟信号。
4. 模拟信号进入VIC2的“bri 0/1/0”后,会先建立Q921及Q931,当Layer1-3都active后,底层ok,模拟信号会到异步口上,模拟信号都要跟异步口对应的。
5. 模拟信号不识别IP的相关参数,因此要先解调,所以到异步口后,会首先去确认是否有Modem,也就是“group-rang 0/387 0/422”,系统会自动找一个可用的分配给这个模拟信号进行解调。
6. 解调后,就是数字信号了,也就是咱们熟悉的0/1,那么接下来就是异步口的PPP协商和PPP认证了
7. 认证通过后,根据配置,会给对端分配地址,这样网络就通了
路由器相关信息
Router#sh isdn status Global ISDN Switchtype = basic-net3 ISDN BRI0/1/0 interface dsl 4, interface ISDN Switchtype = basic-net3 Layer 1 Status: ACTIVE Layer 2 Status: TEI = 74, Ces = 1, SAPI = 0, State = MULTIPLE_FRAME_ESTABLISHED Layer 3 Status: 1 Active Layer 3 Call(s) CCB:callid=2, sapi=0, ces=1, B-chan=1, calltype=VOICE Active dsl 4 CCBs = 1 The Free Channel Mask: 0x80000002 ISDN BRI0/1/1 interface dsl 5, interface ISDN Switchtype = basic-net3 Layer 1 Status: SHUTDOWN Layer 2 Status: Layer 2 NOT Activated Layer 3 Status: 0 Active Layer 3 Call(s) Active dsl 5 CCBs = 0 The Free Channel Mask: 0x00000000 Total Allocated ISDN CCBs = 1 Router#sh line Tty Line Typ Tx/Rx A Modem Roty AccO AccI Uses Noise Overruns Int 0 0 CTY - - - - - 0 0 0/0 - Ready 1 1 AUX 9600/9600 - - - - - 0 0 0/0 - Ready 2 2 TTY 9600/9600 - - - - - 0 0 0/0 - Ready A 0/387 387 TTY - inout - - - 1 0 0/0 - Router#sh modem 0/387 Mdm Typ Status Tx/Rx G Duration TX RX RTS CTS DSR DCD DTR 0/387 V34 Conn 33600/33600 1 00:00:50 - - x Modem 0/387 [line 387], Async0/387, TTY387 V12 Firmware: Exp_V3_12_2 Modem config: Incoming and Outgoing Protocol: LAPM, Compression: V44 Last clearing of "show modem" counters: never 1 incoming completes, 0 incoming failures 0 outgoing completes, 0 outgoing failures 0 failed dial attempts, 0 ring no answers, 0 busied outs 0 no dial tones, 0 dial timeouts, 0 watchdog timeouts 0 no carriers, 0 link failures, 0 resets, 0 recover oob 0 protocol timeouts, 0 protocol errors, 0 lost events 0 TDM errors, 0 local retrains, 0 remote retrains 0 local negotiations, 0 remote negotiations 0 tx chars, 0 rx chars, 0 total retransmissions 0 tx async frames, 0 rx async frames, 0 bad async frames 0 tx reject frames, 0 rx reject frames 0 tx correction frames, 0 rx correction frames 0 MHreq rcvd, 0 MHack rcvd, 0 MHnack rcvd, 0 MHclrd rcvd 0 MHcda rcvd, 0 MHfrr rcvd, 0 T1 time-out 0 QC established, 0 Reached MH limit, 0 Clear down 0 Modem recovery events Modulation type V34 # of connections 1 Protocol type LAPM # of connections 1 Transmit Speed Counters: Connection Speeds 33600 # of connections 1 Receive Speed Counters: Connection Speeds 33600 # of connections 1 Router#sh ip int brief Interface IP-Address OK? Method Status Protocol BRI0/1/0 unassigned YES unset up up BRI0/1/1 unassigned YES unset administratively down down Async0/387 33.33.33.1 YES TFTP up up BRI0/1/0:1 unassigned YES unset down down BRI0/1/0:2 unassigned YES unset down down BRI0/1/1:1 unassigned YES unset administratively down down BRI0/1/1:2 unassigned YES unset administratively down down Group-Async1 33.33.33.1 YES TFTP up up Loopback0 33.33.33.1 YES NVRAM up up
PC相关信息
C:\Users\frank>route print =========================================================================== Interface List 29...........................Dial-up Connection 15...00 21 6a 77 77 77 ......Intel(R) WiFi Link 5300 AGN #2 =========================================================================== IPv4 Route Table =========================================================================== Active Routes: Network Destination Netmask Gateway Interface Metric 0.0.0.0 0.0.0.0 11.100.1.1 11.100.1.13 4245 0.0.0.0 0.0.0.0 On-link 33.33.33.2 51 >>> ...... =========================================================================== C:\Users\frank>ipconfig Windows IP Configuration PPP adapter Dial-up Connection: Connection-specific DNS Suffix . : IPv4 Address. . . . . . . . . . . : 33.33.33.2 Subnet Mask . . . . . . . . . . . : 255.255.255.255 Default Gateway . . . . . . . . . : 0.0.0.0 Wireless LAN adapter 无线网络连接 2: Connection-specific DNS Suffix . : cisco.com IPv4 Address. . . . . . . . . . . : 11.100.1.13 Subnet Mask . . . . . . . . . . . : 255.255.252.0 Default Gateway . . . . . . . . . : 11.100.1.1
在拨号中常用到的debug:
debug hdlc32 isr
debug hdlc32 api
debug modem
debug modem csm
debug confmodem
debug ppp nego
debug isdn events
debug isdn q921
debug isdn q931
debug ppp authentication
debug isdn standard
debug ppp pack
debug dialer
debug dialer detailed
debug dialer even
debug ppp negotiation
debug ppp error
debug ppp subscriber
debug ppp packet