Re: [siprec] Stephen Farrell's Discuss on draft-ietf-siprec-metadata-20: (with DISCUSS and COMMENT)

[Paul Kyzivat <[e-mail]>]

On 3/2/16 10:47 AM, Stephen Farrell wrote:
>
>
> On 02/03/16 15:23, Paul Kyzivat wrote:
>> On 3/2/16 6:08 AM, Stephen Farrell wrote:
>>
>>> (2) 6.10: Don't you need to say to use UUID version 4 with
>>> random numbers and to not use MAC addresses?  IOW, refer to
>>> RFC4122, Section 4.4 for how to generate UUIDs.
>>
>> I don't think we want to restrict to the section 4.4 algorithm. SRCs may
>> need quite a lot of UUIDs. There is no reason to be using a random
>> number generator for each one.
>
> Using a good PRNG for this should be fine and is allowed by 4.4.
> There's no need to block on /dev/random for this anyway:-)
>
>> And there could be cases where two SRCs
>> that are cooperating on recording might want to algorithmically
>> synchronize their uuid generation. For both of these cases the
>> name-based algorithm can work well. For that to be safe it is only
>> necessary that the namespace be unique.
>>
>> So I would rather not be so proscriptive about *how* the UUIDs are
>> generated, as long as they avoid accidental collisions and collisions
>> due to malice.
>
> I'd be fine with allowing that too. I think the main thing is
> to exclude using MAC addresses. So maybe saying "Follow RFC4122,
> Section 4.3 or 4.4" would work?

Looking carefully at 4122: IIUC your objection is to using the algorithm 
in section 4.1? So 4.2 and 4.3 are ok. And I would think 4.5 is also ok? 
(But not the NIL UUID.)

If 4.3 is used, does it matter what algorithm is used to create the name 
space ID?

	Thanks,
	Paul