Cisco IOS Software Releases 12.1 Mainline

Cisco IOS Software Release 12.1(1)EX - No. 1055

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Cisco IOS Software Release 12.1(1)EX


This product bulletin describes the content and delivery of Cisco IOS® software Release 12.1(1)EX on the Cisco Catalyst 6000 Family Multilayer Switch Feature Card (MSFC).  Cisco IOS Release 12.1(1)EX is a special release which only supports the Catalyst 6000 family MSFC router daughtercard and FlexWAN Module (WS-X6182-2PA) with associated port adapters. Release 12.1(1)EX is based on Release 12.1(1)E, but it is available before Release 12.1(1)E is available.

Release 12.1(1)EX adds support for the first time for the Catalyst 6000 FlexWAN module, bringing direct WAN interface support to the Catalyst 6000 Family of switches.  Release 12.1(1)EX runs on the Catalyst 6000 MSFC.  Therefore, an MSFC is required for support of this release.

Cisco IOS 12.1(1)EX release is a short-lived Early Deployment (ED) release based on 12.1E. Cisco IOS 12.1EX releases are created when needed to make features, interfaces, and platforms available before they appear in a subsequent release. Cisco IOS 12.1EX releases do not receive regular maintenance updates, and customers should migrate to a subsequent 12.1E release to receive maintenance releases.

For information about the Cisco IOS software release process, please see Product Bulletin #537, Types of Cisco IOS Software Releases, at:

Before deploying a new software release in a production network, always consult appropriate product-specific documentation, release notes, and field notices, refer to the online defect tracking system, and perform acceptance testing in your own test environment.


Release 12.1(1)EX supports the policy listed in "Cisco Systems Product Support Policy" publication at:

New Features in Cisco IOS Release 12.1(1)EX

Cisco IOS Release 12.1(1)EX includes features listed in Table 1.
Table 1: Cisco IOS Release 12.1(1)EX New Features 
Release Feature
  • With IOS Release 12.1(1)EX, the FlexWAN module supports these port adapters:



              Packet over Sonet (OC-3):

              ATM (with traffic shaping):

              T3/E3 (clear-channel and channelized):



Migration Guide

Table 2 maps Cisco IOS 12.1(1)EX release functionality to subsequent 12.1 releases, illustrating the recommended migration path for maintenance releases.
Table 2: Cisco IOS Release 12.1(1)EX Migration Paths
Functionality in Release Is Next Available In Is Next Available In
12.1(1)EX 12.1(1)E 12.1(3)T

Detailed Information

Catalyst 6000 FlexWAN Module

The FlexWAN module may installed in a Catalyst 6000 family switch that has a supervisor engine with a Multilayer Switch Feature Card (MSFC) and Policy Feature Card (PFC) and running Catalyst 5.4 software or later (the FlexWAN module is not currently supported on the Cisco IOS for the Catalyst 6000 Supervisor software option). The MSFC, in conjunction with the FlexWAN module, provides multiprotocol routing support with full Internet route connectivity for speeds ranging from serial RS-232 to OC-3. The FlexWAN module can accept up to two Cisco 7200/7500 WAN port adapters, which deliver WAN consolidation and extend quality of service (QoS) and traffic management capabilities over WAN segments. The FlexWAN module supports ATM and POS OC-3 links and channelized, multichannel, and clear channel port adapters at speeds from T1/E1 to T3/E3.  The number of FlexWAN modules that may be installed in a Catalyst 6000 switch is limited only by the number of available slots in the chassis.

Multilayer switching (MLS) is a Cisco technology which accelerates the routing of packets and reduces the load of a router by learning and establishing flow information on switch hardware and using it to switch packets at wire speed. Specifically, MLS is an interaction between a Cisco Router and a Catalyst Local Area Network (LAN) Switch that allows wire rate hardware switching at Layer 3 and Layer 4. The FlexWAN module utilizes the MLS technology to provide wire rate hardware switching of IP packets between WAN interaces and any other ports in the Catalyst 6000.  In addition, all other routed protocols are supported on the FlexWAN module, however without MLS switching (packet processing is performed in the main processor without hardware assist).

For more detailed information about platforms and features delivered in Release 12.1(1)EX, please refer to the MSFC 12.1(1)EX release notes at:

Product Numbers and Descriptions

Tables 3 describes the available feature sets, product ordering codes, image names, and memory requirements for Cisco IOS software Release 12.1(1)EX.
Table 3: Cisco IOS Release 12.1(1)EX Feature Sets, Ordering Codes, and Memory Requirements
Platform Software Feature Set Product Code Image Flash DRAM
Catalyst 6000 MSFC IP SC6MSFCC-12.1.1EX c6msfc-isv-mz.121-1.EX.bin 16 MB 64 MB
Catalyst 6000 MSFC IP/IPX SC6MSFCD-12.1.1EX c6msfc-dsv-mz.121-1.EX.bin 16 MB 64 MB
Catalyst 6000 MSFC Desktop SC6MSFCB-12.1.1EX c6msfc-dsv-mz.121-1.EX.bin 16 MB 64 MB
Catalyst 6000 MSFC Enterprise SC6MSFCA-12.1.1EX c6msfc-jsv-mz.121-1.EX.bin 16 MB 64 MB
Catalyst 6000 MSFC InterDomain Routing Feature License  FR-IRC6 16 MB 64MB

The orderable software images contain the following feature sets:

     The jsv, isv, and dsv images support the FlexWAN module.

     The IP feature set includes support for wire speed Layer 2 switching (bridging) and Layer 3 switching (routing). IP routing protocols supported include
     RIPv1, RIPv2, OSFP, IGRP, EIGRP, EGP, BGP4, and IS-IS.

     Note EGP, BGP4 and IS-IS routing protocols require the additional purchase of the InterDomain Routing Feature License (FR-IRC6).

     The IP/IPX feature set adds support for wire speed IPX Layer 3 switching.

     The Desktop feature set adds support for AppleTalk Phase 1/2, DECnet Phase IV, and VINES routing.

     The Enterprise feature set adds support for DECnet Phase V and CLNS/OSI routing.

Posted: Fri Dec 8 14:33:46 PST 2000

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