nanog mailing list archives
RE: Smaller than a /24 for BGP?
From: Robert McKay <robert () mckay com>
Date: Wed, 25 Jan 2023 02:55:44 +0000
On 2023-01-25 00:10, Chris J. Ruschmann wrote:
How do you plan on getting rid of all the filters that don’t accept anything less than a /24? In all seriousness If I have these, I’d imagine everyone else does too.
Allow someone to advertise a covering /24 (and route onward to the longer prefixes) in exchange for being able to 'research' the traffic?
You do want a cover advertisement, but it will hardly ever be used by anyone. It attracts traffic, but before that traffic gets anywhere near the origin it hits the more specific longer prefixes and goes straight there.. probably via your immediate upstream, which it would have anyway.
There are large sections of space that have historically always had cover advertisements - 38.0.0.0/8 for instance. If cogent started accepting /29's in there they'd work perfectly courtesy of 38/8 - with nobody else making any other changes to anything.
Probably before long the other transit ISPs would start accepting the longer prefixes too and you'd have fairly functional multi-homing. The long tail of other ISPs doesn't even matter since they inevitably hand the traffic over to someone who will know what to do with it.
-Rob
Current thread:
- Smaller than a /24 for BGP? Justin Wilson (Lists) (Jan 24)
- Re: Smaller than a /24 for BGP? Ian Chilton (Jan 24)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 24)
- Re: Smaller than a /24 for BGP? Jon Lewis (Jan 24)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 24)
- Re: Smaller than a /24 for BGP? Jon Lewis (Jan 24)
- Re: Smaller than a /24 for BGP? Masataka Ohta (Jan 24)
- Re: Smaller than a /24 for BGP? Jon Lewis (Jan 24)
- RE: Smaller than a /24 for BGP? Robert McKay (Jan 24)
- Re: Smaller than a /24 for BGP? John Levine (Jan 24)
- Re: Smaller than a /24 for BGP? Forrest Christian (List Account) (Jan 24)
- Re: Smaller than a /24 for BGP? Lars Prehn (Jan 25)
- Re: Smaller than a /24 for BGP? Masataka Ohta (Jan 27)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 28)
- Re: Smaller than a /24 for BGP? Donald Eastlake (Jan 28)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 28)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 28)
- Re: Smaller than a /24 for BGP? Masataka Ohta (Jan 28)
- Re: Smaller than a /24 for BGP? William Herrin (Jan 28)