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New Member

3660 as the dialup router

Im currently running a 3660 router with 2 module slot occupied by 2 4 serial ports. I also am employing 2 2511 for dialup. I want to use the 2511 to another site and use the 3660 for my dialup as well. We currently have 4 empty slots.

I need help in choosing the right modules to buy. If I buy a 32 digital modem module, do I also need to buy a 32 port Asynchronous Network Module ? Aconfiguration example will be very much appreciated

Please I need advice and help.

Below is the current configuration of my 2511 routerSuvaDialUpRouter02#sho conf

Using 2172 out of 32762 bytes


version 11.3

service timestamps debug uptime

service timestamps log uptime

service password-encryption


hostname SuvaDialUpRouter02


aaa new-model

aaa authentication login use-radius radius local

aaa authentication ppp use-radius if-needed radius local

aaa authorization exec radius local if-authenticated

aaa authorization network radius local if-authenticated

enable secret 5 $1$bqWV$wMaKBOd6n4jimQWbzn.g0.

enable password 7 045802150C2E


username test password 7 120D000406

ip domain-list

ip domain-list

ip name-server

ip name-server

async-bootp dns-server

async-bootp nbns-server

chat-script cisco-default ABORT ERROR "" "AT Z" OK "ATDT \T" TIMEOUT 30 \c CONNc



interface Ethernet0

ip address

no mop enabled


interface Serial0

no ip address

no ip mroute-cache



interface Serial1

no ip address



interface Group-Async1

ip unnumbered Ethernet0

encapsulation ppp

no ip route-cache

no ip mroute-cache

keepalive 10

async dynamic address

async mode interactive

peer default ip address pool dialin

ppp reliable-link

ppp authentication chap use-radius

group-range 1 16


ip local pool dialin

ip default-gateway

ip classless

ip route


radius-server host auth-port 1645 acct-port 1646

radius-server key RoLalabalavu29


line con 0

line 1 16


autoselect during-login

script dialer cisco-default

login authentication use-radius

modem InOut

transport input all

flowcontrol hardware

line aux 0

line vty 0 4

password 7 15181E1F102E242D3C



Cisco Employee

Re: 3660 as the dialup router

You need to buy 32 Digital module (NM-32DM) only if you have a digital line Channelized T1/E1 coming in the 3660 over which 2511 will dialin..But if you just have analog POTS line coming in at 3660, you just need a NM-32AM to terminate the analog calls from 2511..

config will be nearly the same as you have on 2511 right now (shown above) with just more lines (line 1 32) and "group-range 1-32" under interface group-async 1..

New Member

Re: 3660 as the dialup router

Thanks for the info. One more question. Does this mean that I dont buy the 32-port Asynchronous Network Module ? What i want is to totally isolate the 2511 that we currently use for dialup. I want my user to dial into the 3660 router now. The 2511 will be deployed to two of our main sites where users just dial in to that 2511.

I hope Im clear


Re: 3660 as the dialup router

On the 3660 will either need 30 digital modems (NM-30DM) OR NM-32A with external modems attached.

NOTE: For the NM-30DM in addition will need a channelized T1/E1 versus a NM-32A where will need individual POTS lines connecting to the external modems.

Thanks, Mak.

New Member

Re: 3660 as the dialup router

Thanks for all the info. Im starting to get to understand it very well. I have done some quiries to our Telco provider and the cost of a T1/E1 is quiete expensive. What modules will I need if I just utilise the current 32 analog lines Im currently using for our 2511 ? Do I need to buy a 2 by 16 Analog modems (NM-16AM) with 32 Asynchronous port (NM -32A)

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