Subject: [secdir] Secdir review of draft-ietf-mmusic-duplication-grouping-03

From: Vincent Roca <[email-masked]>
Date: Mon, 18 Nov 2013 15:58:04 +0100

Hello,

I have reviewed this document as part of the security directorate's
ongoing effort to review all IETF documents being processed by the
IESG.  These comments were written primarily for the benefit of the
security area directors. Document editors and WG chairs should treat
these comments just like any other last call comments.

IMHO, the document is Almost ready.

My main comment WRT this I-D is the following:

1- There is no reference to RFC4566 (SDP) security section! This is a pity
as the security considerations are very well addressed in this RFC, much
better than in the present I-D I would say.
Additionally, I don't think that adding duplication grouping to SDP changes
so much the situation WRT SDP security, so this is one more reason to
have this reference.

Otherwise:

2- The authors say that "there is a weak threat". Is the threat weak in the
sense it is unlikely to happen (why?), or is it weak in the sense it will have
limited consequences? In any case, I would be in favor of removing
"weak" altogether.

3- Since we are now all aware of the necessity of making pervasive
monitoring more  complex, it could be useful to say that having some
confidentiality is recommended (in addition to integrity and authentication
of course). This is not discussed in RFC4566 (but it was published in 2006),
so it's worth mentioning it in this I-D (no need to say much).

Non security related comment:

4- The [IC2011] reference should be updated. It's published, and the
volume/number are now known.

Cheers,

   Vincent

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From: "Ali C. Begen (abegen)" <[email-masked]>
Date: Mon, 18 Nov 2013 15:22:33 +0000

Hi Vincent,

> so much the situation WRT SDP security, so this is one more reason to

We can add this, no worries. I think we simply followed RFC 5888 in this section but your point is taken.

> limited consequences? In any case, I would be in favor of removing

It means it is unlikely to happen because if someone can modify the SDP for changing the grouping, it can actually do much worse things by changing other things. 

> so it's worth mentioning it in this I-D (no need to say much).

Personally I dont think anything we say in this draft will have any impact in this regard but I can add this when doing the revision.

> volume/number are now known.

Good point, I thought this was fixed. Thanks.

---

From: Vincent Roca <[email-masked]>
Date: Wed, 20 Nov 2013 08:59:01 +0100

Hi Ali,

> We can add this, no worries. I think we simply followed RFC 5888 in this section but your point is taken.

I've missed this RFC. Anyway, a reference to RFC 4566 is fine as it details
security aspects with a reasonable level of details.

> It means it is unlikely to happen because if someone can modify the SDP for changing the grouping, it can actually do much worse things by changing other things. 

Of course, but "weak" remains ambiguous (unless you say more) and in fact
not that important.

> Personally I dont think anything we say in this draft will have any impact in this regard but I can add this when doing the revision.

Yes, but focusing on integrity and source authentication only suggests
that confidentiality is not an important service. That's my point. A single
sentence saying that it can sometimes be useful to use a secure, encrypted
channel or transport to carry the SDP is sufficient.

Cheers,

   Vincent