Re: [v6ops] RFC7084

[Owen DeLong <[e-mail]>]

On Dec 11, 2013, at 1:45 AM, Alexandru Petrescu <[e-mail]> wrote:

> Le 10/12/2013 18:44, Ole Troan a écrit :
>>>> In no case do I believe that M or O provide any indication about
>>>> IA_PD.
>>> 
>>> You should read RFC 7084 again, then.
>>> 
>>> Standards say what they say, not what you think they should say!
>>> :)
>> 
>> RFC7084 isn't a standard. can we please stop this now. having the M/O
>> debate one more time is unlikely to provide a different result than
>> the previous times we have had this debate.
> 
> I agree we should go past the typical M/O debate, learn from it.
> 
> One way I read the ongoing discussion, if I am not wrong, is that there
> is difficulty created by the lack of a flag specific to IA_PD ("As far
> as I know the M flag is linked only to IA_NA. As far as I can see IA_PD
> is not linked to the M flag at all.”).

> 
> Am I the only to read this as maybe a hint towards necessity of creation
> of a new flag akin to M/O but specific to IA_PD? I.e. it would be allow
> a Router to see whether it may be able to specifically request a
> Delegated Prefix even when it would self-configure its address by other
> means than DHCP.

I don’t see the need. A router which wants a prefix should ask for one.

The worst case is it doesn’t get an answer.

The next worst case is it is denied.

What is the benefit of having a flag to (sometimes) say that prefixes are
available for the asking?

> 
> (in the past some local thought was given about how RA would advertise a
> capability of delegating prefixes, e.g. this 'D' flag in a draft:
> 
>>    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
>>   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>   |     Type      |     Code      |           Checksum            |
>>   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
>>   | Cur Hop Limit |M|O|H|Prf|P|D|r|        Router Lifetime        |
>>   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
> )
> 

I wasn’t around for that discussion, but my guess would be that the discussion
likely came to the same conclusion I did… If you want a prefix, ask. A D flag
wouldn’t really improve anything.

Owen