Re: [Softwires] [BEHAVE] PMTU Discovery and ICMPv6 filtering

Michael Richardson <mcr@sandelman.ca> Thu, 04 February 2010 03:46 UTC

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From: Michael Richardson <mcr@sandelman.ca>
To: Ed Jankiewicz <edward.jankiewicz@sri.com>
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Cc: softwires@ietf.org, Behave WG <behave@ietf.org>
Subject: Re: [Softwires] [BEHAVE] PMTU Discovery and ICMPv6 filtering
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Ed, there are a number of things to say.
First, behaviour 4 is mostly described by RFC4301, I believe.
Yes, section 8.2.1.
If you find it is not available, then you need to talk to your vendors.

Behaviour 3 (which, in IPv4 speak, is essentially not copying the DF
bit), is often necessary, but it can mess up the plpmtu mechanism.

Second, PLPMTUD was publiched by the pmtud WG as RFC4821.
This is the best suggestion.

I wrote about what Freeswan/Openswan KLIPS tried to do, which was a
variation of #3, because we wanted the network to work...   it is at:
    http://www.sandelman.ca/SSW/ietf/ipsec/fragment/draft-richardson-ipsec-fragment.txt

Most of these ideas were incorporated into RFC4821.

-- 
]       He who is tired of Weird Al is tired of life!           |  firewalls  [
]   Michael Richardson, Sandelman Software Works, Ottawa, ON    |net architect[
] mcr@sandelman.ottawa.on.ca http://www.sandelman.ottawa.on.ca/ |device driver[
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