RE: [Idr] why has 4096 bytes limit on BGP messages size?
"Susan Hares" <skh@nexthop.com> Fri, 15 June 2007 14:53 UTC
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Subject: RE: [Idr] why has 4096 bytes limit on BGP messages size?
Date: Fri, 15 Jun 2007 08:53:16 -0600
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Thread-Topic: [Idr] why has 4096 bytes limit on BGP messages size?
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From: Susan Hares <skh@nexthop.com>
To: Pekka Savola <pekkas@netcore.fi>, Danny McPherson <danny@tcb.net>
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Pekka: What is the complexity of the BGP peering at your DFZ? Can you give an overview of the type of updates this represents? Without that information, it is difficult to quantify your data point. Millions of routers in several virtual routers with RD tags may have a different flow pattern of updates. Thanks, Sue -----Original Message----- From: Pekka Savola [mailto:pekkas@netcore.fi] Sent: Friday, June 15, 2007 1:48 AM To: Danny McPherson Cc: idr List Routing Subject: Re: [Idr] why has 4096 bytes limit on BGP messages size? On Thu, 14 Jun 2007, Danny McPherson wrote: > On Jun 14, 2007, at 9:59 AM, Pekka Savola wrote: >> (The header fields already tell the length of the message, so allocating 4K >> buffer for each BGP message (when most messages are much smaller than 4K) >> is probably a waste in many cases.) > > Pekka, > Do you have some references to data supporting your comment here > regarding most messages being smaller than 4K? Yes. I've sometimes taken debugs logs of BGP when a DFZ table flapped and looked at the packets. Here's a plot of BGP Update size versus occurrences (in this about 10-15min trace, 87K BGP updates). BGP Updates are sent by a Juniper T-series router. The smallest is 26B, the largest 4095B. Top 20 sizes (6995 through 1229 occurrences) are all between 58 and 95 bytes. (Not sure if the small attachment gets on the list, but if not, I'll post it somewhere.) -- Pekka Savola "You each name yourselves king, yet the Netcore Oy kingdom bleeds." Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings _______________________________________________ Idr mailing list Idr@ietf.org https://www1.ietf.org/mailman/listinfo/idr
- [Idr] why has 4096 bytes limit on BGP messages si… Fenggen Jia
- Re: [Idr] why has 4096 bytes limit on BGP message… Tony Li
- Re: Re: [Idr] why has 4096 bytes limit on BGP mes… Fenggen Jia
- Re: Re: [Idr] why has 4096 bytes limit on BGP mes… Jeffrey Haas
- Re: [Idr] why has 4096 bytes limit on BGP message… Enke Chen
- Re: [Idr] why has 4096 bytes limit on BGP message… Pekka Savola
- Re: Re: [Idr] why has 4096 bytes limit on BGP mes… Vishwas Manral
- Re: [Idr] why has 4096 bytes limit on BGP message… Erblichs
- Re: [Idr] why has 4096 bytes limit on BGP message… Danny McPherson
- Re: [Idr] why has 4096 bytes limit on BGP message… Danny McPherson
- Re: [Idr] why has 4096 bytes limit on BGP message… Erblichs
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- Re: [Idr] why has 4096 bytes limit on BGP message… Pekka Savola
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- RE: [Idr] why has 4096 bytes limit on BGP message… Susan Hares
- RE: [Idr] why has 4096 bytes limit on BGP message… Susan Hares
- Re: Re: Re: [Idr] why has 4096 bytes limit on BGP… Fenggen Jia
- Re: [Idr] why has 4096 bytes limit on BGP message… Tony Li
- Re: [Idr] why has 4096 bytes limit on BGP message… Curtis Villamizar
- Re: [Idr] why has 4096 bytes limit on BGP message… Vishwas Manral
- RE: [Idr] why has 4096 bytes limit on BGP message… Bhatia, Manav (Manav)