Re: [MMUSIC] Roman Danyliw's Discuss on draft-ietf-mmusic-rfc4566bis-35: (with DISCUSS and COMMENT)

[Paul Kyzivat <[e-mail]>]

Roman,

On 6/19/19 5:11 AM, Roman Danyliw wrote:

> Thanks for the revision to Section 7 to clarify the language within the section.  I still see a conflict between the guidance in Section 5.12 and 7.
> 
> Section 5.12 says:
>     The "k=" line (key-field) is obsolete and MUST NOT be used.  It is
>     included in this document for legacy reasons.  One MUST NOT include a
>     "k=" line in an SDP, and MUST discard it if it is received in an SDP.
> 
> The new text in Section 7 says:
>     SDP MUST NOT be used to convey keying material (e.g., using
>     "a=crypto" [RFC4568]) unless it can be guaranteed that the channel
>     over which the SDP is delivered is both private and authenticated.
> 
> My read is that Section 5.12 says don't use k= and drop it if you see it; and Section 7 says don't use k= unless you can guarantee certain channel properties.  Consider the situation where one has the right channel properties (per Section 7), why would one use k= since Section 5.12 would dictate that this k= would get dropped?

The new section 7 uses a=crypto, which is a different mechanism from k=. 
So I don't see the conflict you are concerned with.

	Thanks,
	Paul