Cisco Cisco IOS Software Release 12.4(23)

Dial Access Network 
Modules

16- and 32-port asynchronous (NM-16A and NM-32A)

All Cisco 3600 series platforms

4- and 8-port synchronous/asynchronous (NM-4A/S and 
NM-8A/S)

All Cisco 3600 series platforms

6- to 30-port integrated digital modems network modules 
(NM-6DM, NM-12-DM, NM-18DM, NM-24DM, 
NM-30DM)

All Cisco 3600 series platforms 
except the Cisco 3631

6 digital modem upgrade (MICA-6MOD)

All Cisco 3600 series platforms 
except the Cisco 3631

8- or 16-port integrated analog network modules (NM-8AM 
and NM-16AM)

All Cisco 3600 series platforms 
except the Cisco 3631

LAN Interfaces

1- and 4-port Ethernet (AUI and 10BASE-T, NM-1E, and 
NM-4E)

All Cisco 3600 series platforms 
except the Cisco 3631

1-port Fast Ethernet (100BASE-TX and 100BASE-FX, 
NM-1FE-TX, NM-1FE-FX, and NM-1FE-FX-V2)

1

All Cisco 3600 series platforms 
except the Cisco 3631

Gigabit Ethernet network module (NM-1GE) with 1 GBIC 
slot

Cisco 3660 only

Fast Ethernet Switch 
Network Modules

16-port Ethernet Switch Module for 2600 or 3600 
(NM-16ESW)

All Cisco 3600 series platforms 
except the Cisco 3631

36-port Ethernet Switch Module (NM-36ESW)

Cisco 3660 only