Re: [homenet] Which IP addresses must be avoided?

Joe Touch <touch@isi.edu> Tue, 17 May 2016 16:50 UTC

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To: Ray Bellis <ray@bellis.me.uk>, homenet@ietf.org
References: <87wpms8zvo.wl-jch@pps.univ-paris-diderot.fr> <5ae48799-cb13-2b68-a4cc-a56b6174ae4f@bellis.me.uk>
From: Joe Touch <touch@isi.edu>
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Date: Tue, 17 May 2016 09:49:39 -0700
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Subject: Re: [homenet] Which IP addresses must be avoided?
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On 5/17/2016 9:35 AM, Ray Bellis wrote:
> However some operators have (had?) "classful" firewall rules that
> prohibit packets that come from IP addresses that would have been
> considered a broadcast address in a pre-CIDR world.

It's been 23 years since pre-CIDR and 15 years since you experienced
this error.

If we can't assume a fix here, then we can't assume any of the IPv6
reserved IDs are actually reserved either - they could easily be in use
by legacy equipment.

I.e,, the Postel principle applies here:

    - avoid assigning these addresses
    - test your equipment to ensure that they allow these addresses
correctly

If only we had compliance testing (again)....

Joe