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Date: Mon, 05 Apr 2004 11:44:47 +0200
From: Anders Lowinger <anders.lowinger@packetfront.com>
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To: Luigi Rizzo <rizzo@icir.org>
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cc: net@freebsd.org
Subject: Re: do we support non contiguous netmasks ?
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Luigi Rizzo wrote:
> Hi,
> i was wondering if anyone knows what kind of support we have
> in FreeBSD networking code, for non contiguous netmasks.
> While it is trivial to support them for interface addresses,
> managing them in the routing table is probably far from trivial
> and I believe also mostly useless... and anyways, i have no
> idea how our kernel code deals with them

Not sure why you wonder? Do you need it?

If we implement a mtrie for faster routing-lookups,
non-contiguous masks need to go.

Not even Cisco implements anything else than contiguous masks,
and I have a very hard time to understand why they are needed.

/Anders