nanog mailing list archives
Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms
From: Saku Ytti <saku () ytti fi>
Date: Fri, 8 Mar 2019 19:18:34 +0200
On Fri, Mar 8, 2019 at 7:07 PM Töma Gavrichenkov <ximaera () gmail com> wrote:
It's been a while since then, and maybe there was a mistake on our side (at least within a perfectly academic context I must assume that there was, as there was no peer review — we were not in academy after all!), but I'm still inclined to, first, see the benchmarks of any proposed piece of hardware that's promising you ECMP with flow labels, second, make any statements about the latter.
1) current implementation - set offset byte to 8 - read 128 bits to memory1 - read 128 bits to memory2 - return hash_function(memory1, memory2) This is _JUST_ for L3 keys, in reality customers want L4 keys too, so it's more expensive. Particularly in IPv6 the L4 keys could be _anywhere_ potentially gigabytes in future, for same reasons in IPv6 you can bypass ACL filters in many cases, because the HW device won't know what the L4 keys are. 2) flow label implementation - set offset to 12 bits - read 20 bits to memory1 - return memory1 Seems cheaper to me. But still not a good solution, as it is AFI specific and requires us to actually use the flow label consistently, which is not universally true. ECMP on embedded ICMP actually would work without any changes anywhere else but the device calculating the hash. -- ++ytti
Current thread:
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms, (continued)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Mark Andrews (Mar 05)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 05)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Joel Jaeggli (Mar 05)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 05)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Töma Gavrichenkov (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Tarko Tikan (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Töma Gavrichenkov (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Töma Gavrichenkov (Mar 08)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 08)
- RE: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms adamv0025 (Mar 12)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 12)
- RE: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms adamv0025 (Mar 12)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 12)
- RE: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms adamv0025 (Mar 12)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Saku Ytti (Mar 12)
- RE: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms adamv0025 (Mar 13)
- Re: ICMPv6 "too-big" packets ignored (filtered ?) by Cloudflare farms Masataka Ohta (Mar 09)