400G forwarding - how does it work?

Saku Ytti saku at ytti.fi
Wed Aug 10 07:07:03 UTC 2022


On Wed, 10 Aug 2022 at 06:48, <sronan at ronan-online.com> wrote:

> How do you propose to fairly distribute market data feeds to the market if not multicast?

I expected your aggressive support for small packets was for fintech.
An anecdote:

one of the largest exchanges in the world used MX for multicast
replication, which is btree or today utree replication, that is, each
NPU gets replicated packet wildy different time, therefore receivers
do. Which wasn't a problem for them, because they didn't know that's
how it works and suffered no negative consequence of this, which
arguably should have been a show stopper if we need receivers to
receive it at a remotely similar time.

Also, it is not in disagreement with my statement that it is not
addressable market, because this marker can use products which do not
do 64B wire-rate, for two separate reason either/and a) port is no
where near congested b) the market is not cost sensitive, they buy the
device with many WAN ports, and don't provision it so that they can't
get 64B on each actually used ports.


-- 
  ++ytti


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