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Re: LCAS and GMPLS

Hi, Adrian

 Thank you for your comment.
 I should have explain my thought more in detail.


> >see anything that forces this limitation. In fact, it would be hard to
> >offer 1:n protection with such a scheme.
>
> In my understanding, the ASSOCIATION ID of ASSOCIATION Object only
> relates protected LSP and protecting LSPs.

Then I am sorry to say that your understanding is wrong.

The Association object is used to associate LSPs.
Clearly, in its use in a protection ID it describes the association for
the purposes of protection. However, the text is carefully worded to
ensure that the object is more widely applicable.
To quote from section 16...
   The ASSOCIATION object is used to associate LSPs with each other.


You originally said...
> > > Current ASSOCIATION objects relates only two connections.
...but you now seem to accept that the Association object can relate more
than one LSP since you say...
> It's OK adoptation of ASSOCIATION Object and ID for 1:n protection.

Thus, I presume that you accept that the Association object could handle
VCAT groups with more than two LSPs.

Yes.
In the case of 1:n protection scheme, all of n back up paths set the primary LSP ID
for their Association IDs. It seems OK the use of association ID.

>   Now, consider the LCAS.
>   Does the LCAS define or have primary connetion ?
>   I think all of conections in LCAS should be equivalent.


Why is primary conneciton valid? LCAS has nothing to do with protection.
The Association object provides an *arbitrary* association ID that is
common across all LSPs in the same group, and unique within the context of
the association source. There is no concept of a primary connection in the
process of association.

But, my concern is the value of Association ID in VCAT.
Different from 1:n protection, generic VCAT group does not have primary connection.
In the case of 1:n protection, we define "primary" connection.

But, in the case of generic VCAT, the Association ID of second and third connection
should be first connection of LSP ID ?
My answer is no.

The first connection in VCAT group can be torn down before the tear down of secondary or third connection.
If the second and third connection use LSP ID of first connection for their Association ID,
the second and third connection of the VCAT group use non-existing LSP ID for their Association ID
in some state.
Do we accept this kind of state ?

Thanks,
Wataru

---------------------------------
Wataru Imajuku
@NTT Network Innovation Labs.
TEL +81-46-859-4315
FAX +81-46-859-5541