Re: [pim] Stephen Farrell's Discuss on draft-ietf-pim-rfc4601bis-05: (with DISCUSS)

[Brian Haberman <[e-mail]>]

Hi Stephen,

On 5/26/15 9:08 AM, Stephen Farrell wrote:
> Stephen Farrell has entered the following ballot position for
> draft-ietf-pim-rfc4601bis-05: Discuss
> 
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> 
> ----------------------------------------------------------------------
> DISCUSS:
> ----------------------------------------------------------------------
> 
> 
> 
> 4601 used IPsec AH for it's MTI security. This removes that and
> points at 5796 which defines how to use ESP for link local
> addresses and with manual keying. That raises one technical
> question and two ickky process questions. The ickky process
> questions are probably best discussed between the IESG at least
> initially in case we don't need to bother the authors/wg with
> 'em.
> 
> (1) I'd like to check that 5796 defines a way in which one can
> secure all PIM messages that are defined here in 4601bis (should
> one want to do that). If there are cases where PIM-SM can be
> used and where there is no well defined security then I think
> that would be a problem. And I think maybe there are such cases.
> Am I wrong? If not, then how does one secure those?

5796 focuses on the link-local messages (i.e., directly-connected
peers), but does say

   Securing the unicast messages can be achieved by the use of a normal
   unicast IPsec Security Association (SA) between the two communicants.

The above refers to the set of PIM messages that are not sent as
link-local.  My opinion is that this is sufficient given the uses of PIM
as defined in 4601.

> 
> (2) Is it ok for an IS to depend on a PS for it's MTI security
> mechanism? (I think it is, but yeah, someone else might not.) 

I don't see why not.

> 
> (3) Is it ok for an IS to not conform to BCP107? (I think it
> depends, and I'm not sure in this case.)

I am not sure how BCP 107 relates since it discusses Guidelines for
Cryptographic Key Management and the crypto stuff is now referred to via
5796.

Regards,
Brian