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RE: WEBINAR TUESDAY: Can We Make IPv4 Great Again?


From: "Jakob Heitz (jheitz)" <jheitz () cisco com>
Date: Tue, 7 Mar 2017 17:46:12 +0000

1.1.1.1.e.f and 2.2.2.2.e.f both get translated to 192.168.e.f.

Some higher layer protocols embed IP addresses into their data.

These points make changing IP so difficult.

In addition, IPv6 has link local addresses.
This one seemingly insignificant detail causes so much code churn
and is probably responsible for 10 years of the IPv6 drag.
Thakfully, site local was deprecated.

Thanks,
Jakob.

Date: Mon, 6 Mar 2017 22:00:45 +0100
From: Baldur Norddahl <baldur.norddahl () gmail com>
To: nanog () nanog org
Subject: Re: WEBINAR TUESDAY: Can We Make IPv4 Great Again?
Message-ID: <5645714e-e468-4655-34cf-6e70aa7cfa26 () gmail com>
Content-Type: text/plain; charset=utf-8; format=flowed

That proposal is far too wordy. Here is the executive summary:

Encode extra address bits in extension headers. Add a network element
near the destination that converts such that the destination IP of a
packet to IP a.b.c.d with extension header containing e.f is translated
to 192.168.e.f. In the reverse direction translate source address
192.168.e.f to a.b.c.d and add option header with e.f.

Executive summary end.

As far as I can tell, the only advantage of this proposal over IPv6 is
that the network core does not need to be changed. You could communicate
with someone that had an EZIP address regardless that your ISP did
nothing to support EZIP.

The disadvantage is that every single server out there would need to be
changed so it does not just drop the option headers on the reply
packets. All firewalls updated so they do not block packets with option
headers. All applications updated so they understand a new address format.

Servers and applications could also confuse TCP or UDP streams that are
apparently from the same source, same port numbers, only thing that
differentiates the streams is some option header that the server does
not understand.

The customers of the ISP that deploys EZIP would not need to update
anything (unless they need to communicate with other poor souls that got
assigned EZIP addresses), however everyone else would. This is not a
good balance. The customers would experience an internet where almost
nothing works. It would be magnitudes worse than the experience of an
IPv6 only network with NAT64.

It is a fix for the wrong problem. Major ISPs have IPv6 support now. It
is the sites (=servers) that are lacking. If Twitter did not deploy IPv6
why would you expect them to deploy EZIP? Why would some old forgotten
site with old song texts in some backwater country somewhere?

We already have better solutions such as CGN with dual stack, NAT64,
DS-Lite, MAP etc.

None of that is discussed in the RFC. Is the author aware of it?

Regards,

Baldur



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