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Re: inter-domain link recovery

  • From: Roland Dobbins
  • Date: Wed Aug 15 04:59:10 2007
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On Aug 15, 2007, at 12:07 AM, Chengchen Hu wrote:

is it always possible for BGP to automatically find an alternative path when failure occurs if exist one? If not, what may be the causes?

Barring implementation bugs or network misconfigurations, I've never experienced an operational problem with BGP4 (or OSPF or EIGRP or IS- IS or RIPv2, for that matter) converging correctly due to a flaw in the routing protocol, if that's the gist of the first question. There are many other factors external to the workings of the protocol itself which may affect routing convergence, of course; it really isn't practical to provide a meaningful answer to the second question in a reasonable amount of time, please see the previous reply.

The questions that you're asking essentially boil down to 'How does the Internet work?', or, even more fundamentally, 'How does routing work?'. I would strongly suggest familiarizing oneself with the reference materials cited in the previous reply, as they provide a good introduction to the fundamentals of this topic.

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Roland Dobbins <[email protected]> // 408.527.6376 voice

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