Conflict between RA and DHCP in MIF case

Hui Deng <denghui02@gmail.com> Mon, 14 November 2011 01:46 UTC

MIME-Version: 1.0
Date: Mon, 14 Nov 2011 09:46:47 +0800
Message-ID: <CANF0JMCo8ZnXtY7DKcoeGApYKu0Enq=O-DFvSmrmkjpSUWzB9g@mail.gmail.com>
Subject: Conflict between RA and DHCP in MIF case
From: Hui Deng <denghui02@gmail.com>
To: ipv6@ietf.org, MIF Mailing List <mif@ietf.org>, dhc WG <dhcwg@ietf.org>
Content-Type: multipart/alternative; boundary="20cf303f6c8036f66204b1a80bca"
Precedence: list

Hello 6MAN and DHCP,

Especially thanks *Wes Beebee*, Hemant Singh, Brian Carpenter, Alex and
Ted's discussion.

MIF is going to discuss the confliction between RA and DHCP on tuesday
afternoon MIF session (15:20-17:00)
the author Tomasz has propose below resolution:

The problem is about potential conflict between RA and DHCP. Our
proposed answer is as follows:

RA provides configuration to all hosts in a network. DHCP can provide
configuration on a per host basis. Therefore it may be useful to use
DHCP to "override" configuration for some hosts in a network (e.g.
engineering department has extra routes defined for a lab network). As
such, DHCP should be preferred.

However, there is also a matter of security. Both RA and DHCPv6 can be
secured. If SEND is deployed, RA is more trustworthy than DHCP, so it
should be preferred. Finally, there is such thing as secure DHCP, so if
both RA and DHCP are secure, prefer SEND. I must admit that I never
heard about any realistic deployments of secure DHCP, but it will change
over time.

This approach can be summed as: favor secure, favor DHCP. Or to be more
explicit, there's a complete list of all cases:
a) RA vs DHCP => prefer DHCP
b) RA(SEND) vs DHCP => prefer RA
c) RA vs secure DHCP => prefer DHCP
d) RA(SEND) vs secure DHCP => prefer DHCP

Does it sound reasonable?

This approach is very similar to what was described in DNS configuration
over RA and DHCP (except the part about both RA and DHCP being secure
that is not covered in RFC6106).

To summarize the discussion so far, Ted Lemon on MIF list agreed that
DHCP should be preferred. Herman Singh on 6MAN list suggested to go look
at what DNS over RA proposes and use the same approach. RFC6106, section
5.3.1covers cases a) and b). c) and d) are logical extension that takes
DHCPv6 security into consideration. My understanding is that proposed
solution will be satisfactory to everyone.

Conflict between RA and DHCP in MIF case Hui Deng
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Karl Auer
Re: Conflict between RA and DHCP in MIF case Karl Auer
Re: [mif] Conflict between RA and DHCP in MIF case Brian E Carpenter
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Karl Auer
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Mark Andrews
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Karl Auer
Re: Conflict between RA and DHCP in MIF case Doug Barton
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Mark Andrews
RE: [dhcwg] Conflict between RA and DHCP in MIF c… Hemant Singh (shemant)
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
RE: [dhcwg] Conflict between RA and DHCP in MIF c… Hemant Singh (shemant)
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Mohacsi Janos
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Karl Auer
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ole Troan
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Thomas Narten
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Marc Blanchet
Re: [dhcwg] Conflict between RA and DHCP in MIF c… Ted Lemon
Re: [mif] [dhcwg] Conflict between RA and DHCP in… Tao Sun