nanog mailing list archives
Re: What's the point of prepend communities?
From: Christopher Morrow <morrowc.lists () gmail com>
Date: Thu, 26 Oct 2017 14:50:54 -0400
On Thu, Oct 26, 2017 at 2:47 PM, Jason Lixfeld <jason+nanog () lixfeld ca> wrote:
Hi Bill,On Oct 26, 2017, at 2:37 PM, William Herrin <bill () herrin us> wrote: BGP routing is based on "distance". Distance in BGP is primarilycalculated as the number of ASNs in the AS Path. Prepends make a path more distance, encouraging routers to choose a different path if one is available. I understand how prepends fit in the context of best path selection, but my question was more the difference between a customer signalling the ISP to prepend their AS using a BGP community stamped to a prefix vs. the customer prepending their own AS instead.
blame shifting? avoiding instances where a third party filters: <ispasn> ?$ vs <ispasn> .*$ or just people's particular picadellos.
Current thread:
- What's the point of prepend communities? Jason Lixfeld (Oct 26)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- Re: What's the point of prepend communities? Jason Lixfeld (Oct 26)
- Re: What's the point of prepend communities? Christopher Morrow (Oct 26)
- Re: What's the point of prepend communities? Job Snijders (Oct 26)
- Re: What's the point of prepend communities? Jason Lixfeld (Oct 26)
- Re: What's the point of prepend communities? Rob Foehl (Oct 28)
- Re: What's the point of prepend communities? Jason Lixfeld (Oct 26)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- RE: What's the point of prepend communities? Naslund, Steve (Oct 26)
- Re: What's the point of prepend communities? William Herrin (Oct 26)
- Re: What's the point of prepend communities? Brett Frankenberger (Oct 26)
- Re: What's the point of prepend communities? Steve Dodd (Oct 28)
- Re: What's the point of prepend communities? Leo Bicknell (Oct 26)
- Re: What's the point of prepend communities? Clinton Work (Oct 26)