bgp update destroying transit on redback routers ?

Igor Ybema igor at
Thu Dec 1 17:08:54 UTC 2011

> And what to do with 4-byte AS-numbers then? That would explain the 8 bytes.

Looking futher:

Two new attributes, AS4_PATH and AS4_AGGREGATOR, are introduced that
can be used to propagate four-octet based AS path information cross
BGP speakers that do not support the four-octet AS numbers.

However this router is AS4 capable, but probably fails to understand a
4-byte AS in the normal AGGREGATOR attribute. If I understand
correctly a AS4 capable router should understand when announcing that
to it's peer.

I'm I correct? Should I file this as a bug? (redback/ericsson is
already looking also)

regards, Igor

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