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BGP - "Remove Private AS" function

Posted: Mon Feb 22, 2010 6:19 pm
by mangust
I can’t find anything regarding "Remove Private AS" function?
Could anybody give me a brief explanation about this function?

Re: BGP - "Remove Private AS" function

Posted: Mon Feb 22, 2010 6:45 pm
by netrat
http://www.cisco.com/en/US/tech/tk365/t ... 3f27.shtml
http://www.debugall.co.uk/2009/02/11/bg ... rivate-as/

From the cisco website
Private autonomous system (AS) numbers which range from 64512 to 65535 are used to conserve globally unique AS numbers. Globally unique AS numbers (1 - 64511) are assigned by InterNIC . These private AS number cannot be leaked to a global Border Gateway Protocol (BGP) table because they are not unique (BGP best path calculation expects unique AS numbers; see BGP Best Path Selection Algorithm for more information on BGP path selection). For this reason, a new feature was added in Cisco IOS® Software release 10.3 and later, which allows the stripping of private AS numbers out of the AS_PATH list before the routes are propagated to a BGP peer.

Re: BGP - "Remove Private AS" function

Posted: Tue Feb 23, 2010 12:23 am
by Chupaka
it can be found in Manual in the Wiki, as I stated in another topic...