Re: [v6ops] Operational Implications of IPv6 Packets with Extension Headers

Fernando Gont <> Mon, 14 September 2020 17:46 UTC

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To: Vasilenko Eduard <>, tom petch <>
Cc: IPv6 Operations <>
References: <> <20200729084351.GG2485@Space.Net> <> <> <> <> <> <> <> <> <> <> <>
From: Fernando Gont <>
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Date: Mon, 14 Sep 2020 14:46:01 -0300
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Subject: Re: [v6ops] Operational Implications of IPv6 Packets with Extension Headers
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Hello, Eduard,

On 14/9/20 08:55, Vasilenko Eduard wrote:
> Hi all,
>> And then there is the future; should more Extension Headers be
>> allocated, should they be constrained to avoid the difficulties
>> raised here?  The I-D, for me, lacks an ending, lacks a look
>> forward.
> I was discussing off-line with Fernando for long time about last
> Tom's comment. No success yet - no agreement to make any predictions
> or recommendations, 

Explaining the present is enough work as to get into trying to predict 
the future :-) . As for recommendations, other that the general thoughts 
I offered to Tom, I'm not sure we'd be able to make any other 
*realistic* recommendations.

> Just "raise awareness". I personally strongly
> suspect that a flood of new EH functionality that is in development
> now would greatly increase drop rate, because not all nodes would
> support everything needed at proper time.

If such functionality is to be employed in the public Internet, then... 

But my understanding is that it is not. In such case, "your networks, 
your rules, your problem", I guess.

> Business is very restricted
> to something 7-10 years (depends on network layer) to refresh
> equipment, even if there is an EOS pressure. Current EH innovation is
> much faster. And additionally it overlays on slowdown of traffic
> growth (it was +50% just 2 years ago, 30% last year, 25% is probable
> this year) - would be more and more difficult to justify
> rip-and-replace.

I'd probably agree.

Now, what do you expect us to do or say about it?

Fernando Gont
SI6 Networks
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492