Cisco Cisco IOS Software Release 12.4(23)

This section contains the following sections with information that is specific to the Cisco 2800 series 
routers:

Cisco IOS Release 12.3(8)T4 introduces and supports the Cisco 2800 series integrated services routers.

The Cisco 2800 series integrated services routers include the Cisco 2801, Cisco 2811, Cisco 2821, and 
Cisco 2851 routers. These routers differ as follows:

Cisco 2801 routers support two HWIC/WIC/VIC/VWIC slots capable of supporting double-wide 
HWICs, one WIC/VWIC/VIC slot, one VWIC/VIC (voice only) slot, two advanced integration 
modules (AIMs), two packet voice data modules (PVDMs), two Fast Ethernet connections, and 
16 ports of IP phone power output.

Cisco 2811 routers support one single network module enhanced (NME), four single or two double 
high-speed WAN interface cards (HWICs), two AIMs, two PVDMs, two Fast Ethernet connections, 
and 24 ports of IP phone power output.

In Cisco 2821 routers, the network module slot adds support for a single network module enhanced 
extended (NME-X), and an additional slot supports an extension voice module (EVM); three 
PVDMs are supported; the LAN ports support two Gigabit Ethernet ports; and 36 ports of IP phone 
power output are available.

In Cisco 2851 routers, the network module slot adds support for network module double-wide 
(NMDs) and network module enhanced extended double-wide (NME-XDs), and the IP phone power 
output is increased to 48 ports.

A High Density Extension Module (HDEM) operates in the EVM slot on the Cisco 2821 and Cisco 2851 
routers. The EVM slot supports additional voice services and density without consuming the network 
module slot on those routers.

For memory recommendations for the Cisco 2800 series routers in Cisco IOS Release 12.4, see the 

Cisco IOS Release 12.4 supports the following Cisco 2800 series routers:

Cisco 2801

Cisco 2811

Cisco 2821

Cisco 2851