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New Member

Install router with async interfaces.


We want to migrate 30 computers with modems in it. Currently they dial into a NT server but we want to migrate them to a Cisco 1800.

I have experience with ISDN router-router connections, but not with computer async-router connections.

Do I need to define all type of modems that these computers are using to create a rule set per computer in the Cisco router? Isn't possible to create a simple config that's useful for all the 30 computer modems to dial-in?

Below I have a sample of the first configuration. what do I still have to add? Spefic modem commands?


ip dhcp excluded-address


ip dhcp pool Async0/1/0

import all



lease 0 4


username test password test345




interface Async0/1/0

description asyn 1/0

no ip address

no ip redirects

no ip unreachables

no ip proxy-arp

encapsulation ppp

no ip route-cache cef

no ip route-cache

dialer in-band

dialer pool-member 1

async mode dedicated


interface Dialer1

ip address

encapsulation ppp

no ip route-cache cef

no ip route-cache

dialer in-band

dialer-group 1

no cdp enable

ppp authentication pap


line 0/1/0

access-class 1 in

login local

modem InOut

autoselect ppp

stopbits 1

speed 115200

flowcontrol hardware


I hope somebody can help me, I'm a bit of lost :-)

Thanks in advance!




Re: Install router with async interfaces.


Do clarify whts the access-list which you have defined and configured under line 0/1/0? Any specific reason attached to that to keep that under the line config ?

Also for information sake do revert the kinda module being installed in your router.

do find some the supporting docs related to async modem configs and modem strings which i feel may help u out ..


New Member

Re: Install router with async interfaces.

Thanks for the reply. Well, the ACL on the line interfaces are overkill.

About the problem. I have a Cisco 1800 with 2 ingrated modems. So a laptop with a buil-in modem wants to dial directly into the Cisco router. But do I need to define the kind of modem of the laptop in my Cisco router? Isn't there a global config for most of the modems?

As attached a diagram.

Re: Install router with async interfaces.


we have done a similar kinda setup for one of our customer quite sometime back using NM-8AM module in 2600 router and i feel we didnt do any extra kinda configs as such.

Are you facing some issues with the configs or any probs ? did u try out debugging where you are getting stuck up ?


New Member

Re: Install router with async interfaces.

sh version of the router:

Cisco IOS Software, 1841 Software (C1841-IPBASE-M), Version 12.3(14)T2, RELEASE SOFTWARE (fc4)

Technical Support:

Copyright (c) 1986-2005 by Cisco Systems, Inc.

Compiled Wed 11-May-05 13:31 by hqluong

ROM: System Bootstrap, Version 12.3(8r)T8, RELEASE SOFTWARE (fc1)

dialout_hme01 uptime is 21 hours, 14 minutes

System returned to ROM by power-on

System image file is "flash:c1841-ipbase-mz.123-14.T2.bin"

Cisco 1841 (revision 5.0) with 114688K/16384K bytes of memory.

Processor board ID FCZ092322H4

2 FastEthernet interfaces

2 Serial interfaces

1 ISDN Basic Rate interface

2 terminal lines

DRAM configuration is 64 bits wide with parity disabled.

191K bytes of NVRAM.

31360K bytes of ATA CompactFlash (Read/Write)