Subject: PANA protocol based on IKEv2?

From: <[email-masked]>
Date: Tue, 24 Jun 2003 16:55:33 +0300

Hi,

I was reading past PANA discussions, and I got this wild 
idea... since much of the discussion seems to be related to 
rather simple message formatting and other protocol issues,
why not "borrow" these from an existing protocol for setting
up SAs for other protocols, namely IKEv2?

Let's see how this could be done:

- We still need a PANA-specific discovery protocol (multicast
  or something), but it can be quite simple.

- For the rest of the protocol, we can copy message structures
  from IKEv2. In the CREATE_CHILD_SA ("Phase 2") exchange we
  just replace the IPsec proposals with proposals for something 
  else (we're not setting up IPsec AH/ESP security association).
  We could define proposal types for e.g.

  - "bootstrap IKEv1 to enforcement point 10.1.2.3; shared secret
     keying material derived according to usual IKEv2 rules"
  - "bootstrap secure DHCP to DHCP server 10.1.2.3"
  - "bootstrap some L2 crypto, <list of parameters/transforms/whatever>"

- What we could borrow from IKEv2?

  - Message formatting 
  - Message protection (something not included in Diameter!)
  - EAP support (and cryptographic binding)
  - "Phase 2" proposal structures (IKEv2 has a nested syntax for 
    proposals, supporting AND/OR (e.g. (X and Y) or Z), attributes 
    for proposals, etc.)
  - How keys for other SAs are derived from IKEv2 SA
  - Cookies for DoS protection
  - Retransmissions
  - Error messages
  - Disconnect indication/session revocation
  - Periodic refresh messages
  - BTW, IKEv2 can also assign IP addresses to the client,
    but maybe this is not needed.

  (Note that this list includes much more than we could
  borrow from Diameter, and the main point is not
  message formatting)

- What we would need to do (at least)

  - Define suitable proposal structures for whatever protocols
    we want to bootstrap using the PANA SA.
  - Probably define new Identification payload types for MAC-address
    type Device Identifiers.
  - Specify exactly how re-authentication and disconnect/revocation
    works (IPsec SAs are unidirectional, so they work a bit 
    differently)

Ok, I said this was a wild idea :) 
Any comments are most welcome!

Best regards,
Pasi