Re: [CGA-EXT] [dhcwg] Follow up request for review of draft-ietf-csi-dhcpv6-cga-ps

Ted Lemon <Ted.Lemon@nominum.com> Tue, 14 September 2010 21:20 UTC

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From: Ted Lemon <Ted.Lemon@nominum.com>
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Date: Tue, 14 Sep 2010 17:21:05 -0400
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Cc: cga-ext@ietf.org, Ralph, Droms <rdroms.ietf@gmail.com>
Subject: Re: [CGA-EXT] [dhcwg] Follow up request for review of draft-ietf-csi-dhcpv6-cga-ps
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We've talked about the topics in this draft before at the DHC working group.   I just reread it, and the only thing I object to about it is the thing I've always objected to about it when it's come up in DHC meetings--the idea of offloading CGA generation work to the DHCP server.

This idea doesn't make sense to me from a security perspective--based on my probably naive understanding of CGA, it seems like this would mean that the private key would have to be sent over the wire in the clear.

I'd be happy to see this draft advance if the text about generating keys on the DHCP server were taken out.