nanog mailing list archives
Re: Order of ASes in the BGP Path
From: "Steven M. Bellovin" <smb () cs columbia edu>
Date: Mon, 29 Aug 2005 15:25:52 -0400
In message <ce8d9033050829094562f3dc2e () mail gmail com>, Abhishek Verma writes:
Hi, Is the order of AS numbers (except for perhaps the first one which denotes the AS the route was originated from) in the AS_PATH in BGP important? In fact, does anybody even care for the first AS number that appears in the Path? AFAIK, AS numbers in the BGP serves two purposes. It helps in loop detection and it helps us count the AS Path length. If this is the case then the order should not really matter much. My question is that whether the operators care if the order, for some reason changes? Eg. Legend: {} denotes the sequence, while [] denotes the set Path {1 2} [3 4] {5} Would somebody mind if this was represented as {1 2 5} [3 4] ?
Any of the proposed BGP security schemes would have trouble with reordering. --Steven M. Bellovin, http://www.cs.columbia.edu/~smb
Current thread:
- Re: Order of ASes in the BGP Path, (continued)
- Re: Order of ASes in the BGP Path Randy Bush (Aug 29)
- Re: Order of ASes in the BGP Path Abhishek Verma (Aug 29)
- Re: Order of ASes in the BGP Path Stephen J. Wilcox (Aug 30)
- Re: Order of ASes in the BGP Path Jake Khuon (Aug 30)
- Bellsouth.net Outage? Alan Spicer (Aug 30)
- Re: Bellsouth.net Outage? Jon Lewis (Aug 30)
- Re: Order of ASes in the BGP Path Randy Bush (Aug 29)
- Re: Order of ASes in the BGP Path Tom Sanders (Aug 29)
- Re: Order of ASes in the BGP Path Paul Jakma (Aug 29)
- Re: Order of ASes in the BGP Path Abhishek Verma (Aug 30)
- Re: Order of ASes in the BGP Path Paul Jakma (Aug 29)
- Re: Order of ASes in the BGP Path Tom Sanders (Aug 29)