Server Fault is a question and answer site for system and network administrators. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Looking at a used Cisco 1841 router with the following feature/package "code"; I'm assuming there's a T1 interface and 128MB of Flash RAM, but the rest I'm not sure of:


Really want to know how many Ethernet interfaces and what speed, IPSec capable/how many, etc.

share|improve this question
up vote 1 down vote accepted

IP Base is the IP Base IOS image. This dictates which features you will have available to you (and IPSec isn't in IP Base).

32FL is 32MB of Flash... this is how much space you have to store IOS images. As long as IOS supports the size of CompactFlash, you can use just about any CF card... just format it with IOS.

The Cisco 1841 Datasheet contains most of the other answers you are looking for (the 1841 as two 10/100 ethernet ports).

If you're looking for IPSec, you need a k9 image (either Advanced Security or Advanced IP Services). See the IOS Packaging Bulletin for the big picture of how Cisco organizes features into images.

share|improve this answer

This document from Cisco should have everything you need:

FEATURES • T1 or fractional T1 network interface

• Wet T1 support (not available on WIC-1DSU-T1)

• N x 64 kbps or N x 56 kbps nonchannelized data rates (N = 1 to 24)

• Standards-based, including ANSI T1.403 and AT&T Publication 62411

share|improve this answer
  • WIC-1DSU-T1-V2 --> has T1 WIC module with integrated DSU (version 2)
  • IP BASE --> IOS image type; note does not specify IOS ver (as mentioned, no encryption; IP-only, does not support IPv6) - if you have a CCO acct, you may d/l another IOS type, but it must fit in Flash
  • 32FL --> 32MB Flash (IOS files stored in Flash; this is kind of a small amt)
  • 128DR --> 128MB DRAM (memory; IOS runs in DRAM, + routing tables, etc.)
share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.