Four byte AS number support in Cisco IOS

Last week IOS release 12.4(24)T appeared on CCO. One of the significant improvements in that release (I can’t manage to get enthusiastic about new kludges to support the SIP morass) is the support for 4-byte BGP AS numbers.

Finally an enterprise network that uses Cisco routers to connect to the Internet can use the new AS numbers distributed by the regional registries (assuming you’re brave enough to run 12.4(24)T on your production gear). The Service Providers using 7600 routers will have to wait … corresponding 12.2SR release is not yet available.

Hat tip to Tassos @ CCIE in 3 months: he was the first to write about this feature.

2 comments:

  1. Hi everyone,

    Can I run 4 byte as number on catalyst 3750, I checked cisco site and there was not available ioses

    ReplyDelete
  2. So, you've got the answer ;)

    Seriously, if you need to run public BGP, it might be better to use a router.

    ReplyDelete

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Ivan Pepelnjak, CCIE#1354, is the chief technology advisor for NIL Data Communications. He has been designing and implementing large-scale data communications networks as well as teaching and writing books about advanced technologies since 1990. See his full profile, contact him or follow @ioshints on Twitter.