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New Member

ISDN modem from PC to Cisco 3661

Hi there,

I got a PC with an ISDN modem, which dial to a Cisco 3661 equippped with a CT1 modem. There are 24 MICA digital modem inside the Cisco 3661 router. There is no problem for ananog modm dialing into this Cisco 3661 router. However, I got a problem for ISDN modem dialing into this Cisco 3661 router. May I ask how can I handle those dialin call from both analog modem and ISDN modem with the same ISDN-23 line? Do I need to extract certain MICA digital modem for calls coming from ISDN modem?

many thanks



Re: ISDN modem from PC to Cisco 3661

Analog modem calls are redirected to the modem pool by the command isdn incoming-voice modem. To handle digital calls you need to configure a dialer interface. Config should look like this:

interface Dialer1

bandwidth 64

ip unnumbered Loopback0

no ip directed-broadcast

encapsulation ppp

no ip route-cache

no ip mroute-cache

dialer in-band

dialer idle-timeout 600

dialer enable-timeout 2

dialer-group 1

no peer default ip address

no fair-queue

no cdp enable

ppp authentication pap

ppp multilink

Depending on your demands, the exact config may be different, this should get you going.



New Member

Re: ISDN modem from PC to Cisco 3661


Do u mean that I need to divide the ISDN line into two portions? One for ISDN modem, and the other for analog modem? May I ask how what are the commands for for achieving this goal?

many thanks


Cisco Employee

Re: ISDN modem from PC to Cisco 3661

Here is the link which has a sample config for "Configuring an Access Server with PRIs for Incoming Multilink Async and ISDN Calls". It is for the AS5300 but the config will be the same for 3600 routers too.

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