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Message-ID: <9bce16843dcc698740d90d8963a1a55516fb1d39.camel@sipsolutions.net>
Subject: Re: [PATCH 0/3] Mesh Fast xmit support
From:   Johannes Berg <johannes@sipsolutions.net>
To:     "Sriram R (QUIC)" <quic_srirrama@quicinc.com>, nbd@nbd.name
Cc:     "linux-wireless@vger.kernel.org" <linux-wireless@vger.kernel.org>
Date:   Fri, 01 Jul 2022 11:27:17 +0200
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> =C2=A0=C2=A0Initially it was set it to a default size of 50 when RFC was =
sent.
> There was a suggestion to
> make it configurable where users could configure this cache size
> proportional to the required/anticipated network capacity.

Oh, right, I missed that this was in the discussion earlier.

The question is what are you afraid of? I mean, even setting it to 500
wouldn't be a huge amount of memory use (~50k), and probably mostly
sufficient regardless of the network? And if you never see all those
nodes, then it wouldn't use all that memory either.

Timing out old entries will also keep memory usage down.

So are you worried about worst-case behaviour in attacks, e.g. somebody
attempting to join the mesh? But then if you're worried about that I
guess you have bigger problems (and should be using secure mesh), such
as the number of station entries?

Or an attacker mutating their Ethernet address behind some gateway? But
they still need to convince the station to even want to send traffic
there...

But even then, setting a much higher limit than 50 should cope with
these cases, while giving enough breathing room for the real usage?

johannes