[core] Comments on draft-ietf-core-oscore-groupcomm-05

[Jim Schaad <[e-mail]>]

This is not a full review, I did a fast look at the differences in between
-04 and -05 and am commenting on these.

1.   The addition of two optional parameters in the aad_array in section
3.1.  In terms of have a deterministic string result this is considered bad
practice as if only one of them is supplied, it could be confused with the
other one.

2.  Who is supposed to validate the parameters dealing with signatures?  Is
this the responsibility of the KDC or does each entity need to do this?  Is
there an optimization that can be applied so that all of these parameters
don't need to be distributed with the rest of the public key fields at a
later date?

3.  I am not sure why RSA-OAEP in the tables, I have never heard of anybody
using these as signature algorithms.

4.  Why did you insert the OSCORE_options field into the aad_array before
the options field?  It would be cleaner to have it at the end to minimize
the differences between the structures.

5.  Just what is the type in section 9.2 for  EdDSA?

Jim