Re: [CCAMP] Generalized Labels for the Flexi-Grid in LSC Label Switching Routers

btw sorry for being pedantic, G.697 Appendix V.1 state a 32 bits wavelength ID. So are we already buying a larger dress?

On 04 Feb 2014, at 12:18, Adrian Farrel <adrian@olddog.co.uk> wrote:

> I think I see a general set of agreements coming along.
> 
> Appendix V.1 gives an example of needing 9 bits to encode m.
> Although an Appendix is not part of the normative spec, we might assume two things from this appendix:
> 1. Currently only up to 8 bits are needed
> 2. The is a trend toward more than 8 bits
> 
> As Gabriele suggests, 16 bits is a lot. So I don't think we need to worry about extensibility if we go there.
> 
> I will update the I-D to make m 16 bits wide, and I will (continue to) say that the definition of m is per the slot width formula defined in G.694.1. This makes no comment within the draft on the legitimate values of m, but defers the data plane specification to the ITU-T.
> 
> As to describing such things in the framework, I would be opposed to an IETF document that describes the flexi-grid data plane in any detail. That is, IMNSHO, not our remit and not the scope of CCAMP. But we could ask the AD for an opinion on that ;-)
> 
> A
> 
>> -----Original Message-----
>> From: CCAMP [mailto:ccamp-bounces@ietf.org] On Behalf Of Huub van Helvoort
>> Sent: 03 February 2014 14:26
>> To: Ramon Casellas; Oscar González de Dios
>> Cc: CCAMP
>> Subject: Re: [CCAMP] Generalized Labels for the Flexi-Grid in LSC Label Switching
>> Routers
>> 
>> Hola Ramon,
>> 
>> G.694.1 does not define a maximum value for "m".
>> 
>> However G.697 gives in Appendix V.1: Wavelength ID.
>> "m" = 9 bits (m is encoded as a 9-bit unsigned integer).
>> 
>> Regards, Huub.
>> 
>> 
>>>> I am happy if we don't need to do so. But is this not better than
>>>> defining/ extending a new label format when ITU-T changes the data plane?
>>> 
>>> Dear all,
>>> 
>>> I may be missing something (apologies in advance if it is the case) and
>>> since I don't have them here right now, for the sake of this discussion,
>>> maybe could anyone point to the relevant part of the document(s) e.g.
>>> G.694.1 / G.872 etc. where it is said that the value of m is bound to 256?
>>> We are aware of the concept of frequency slot, nominal central
>>> frequencies (n, and their values) and the concept of frequency slot
>>> width, but I cannot recall now such a bound.
>>> 
>>> Thanks
>>> R.
>>> 
>> 
>> 
>> --
>> **************************************************************
>> ***
>>               请记住，你是独一无二的，就像其他每一个人一样
>> _______________________________________________
>> CCAMP mailing list
>> CCAMP@ietf.org
>> https://www.ietf.org/mailman/listinfo/ccamp
> 
> _______________________________________________
> CCAMP mailing list
> CCAMP@ietf.org
> https://www.ietf.org/mailman/listinfo/ccamp