Re: [v6ops] How do you solve 3GPP issue if neither operator nor handset supports PD?

Philip Homburg <> Mon, 30 November 2020 17:09 UTC

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Subject: Re: [v6ops] How do you solve 3GPP issue if neither operator nor handset supports PD?
From: Philip Homburg <>
In-reply-to: Your message of "Mon, 30 Nov 2020 16:08:37 +0000 ." <>
Date: Mon, 30 Nov 2020 18:08:53 +0100
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> your statements
> don't match with the reality of Duplicate Address Detection.  DAD
> is required if there is not going to be any differentiation between
> LLA generation mechanisms. 

DAD is required, but DAD cannot detect things that aren't there.

If two hosts have different MAC addresses then their EUI-64 IIDs cannot collide.

By and large the implementation of the pseudo random IIDs generators is good
enough the collision don't occur.

Of course, there are plenty of lines that end up in loopback. But in that case
your flags scheme would not help either.

> I want to be able to avoid DAD whenever
> possible - certainly in the aviation domain this is very important.
> And, having the LLA Type field would aid in capitalizing on cases
> when DAD can be avoided.

You are trying to burden every IPv6 system with the specific needs you have
for aviation. That is a bad trade off.

Other link types still have to do DAD, so adding those flags doesn't help at all.

If you know that OMNI IIDs are unique, then just specify that on OMNI links only
OMNI IIDs are used and disable DAD.

I think 6lo does something similar for EUI-64.