Re: [CCAMP] [RTG-DIR] RtgDir review: draft-ietf-ccamp-general-constraint-encode-16.txt

[Leeyoung <[e-mail]>]

Lou,

OK, How about:

OLD 

... There may be more than one matrix associated with
   a node as the node can partition the switch matrix into several sub-
   matrices for various reasons such as incremental updates, etc. When
   the matrix is partitioned into sub-matrices, it is envisioned that
   they are mutually exclusive to one another in representing which
   ports/labels are associated with each sub-matrix. This implies that
   two matrices will not have the same {src port, src label, dst port,
   dst label}.

   Each sub-matrix is assigned a unique Matrix ID to represent a 
   mutually exclusive set of {src port, src label, dst port, dst label} 
   from other sub-matrices.

NEW: 

... There may be more than one matrix associated with
   a node as the node can partition the switch matrix into several sub-
   matrices for various reasons primarily to limit the size of any 
   individual information element used to represent the matrix or allow 
   incremental updates, etc. When the matrix is partitioned into 
   sub-matrices, it is envisioned that they are mutually exclusive to 
   one another in representing which ports/labels are associated with 
   each sub-matrix. This implies that two matrices will not have the 
   same {src port, src label, dst port, dst label}.

   Each sub-matrix is assigned a unique Matrix ID to represent a 
   mutually exclusive set of {src port, src label, dst port, dst label} 
   from other sub-matrices.

Would this be Ok with you? Then I will publish a revision upon your approval.

Thanks,
Young

-----Original Message-----
From: Lou Berger [mailto:[e-mail]] 
Sent: Tuesday, February 03, 2015 7:59 AM
To: Leeyoung
Cc: '[e-mail]'; '[e-mail]'; '[e-mail]'; Tomonori Takeda; [e-mail]
Subject: Re: [RTG-DIR] RtgDir review: draft-ietf-ccamp-general-constraint-encode-16.txt

Young,

I guess I didn't see the new text as substantively different or more
informative than preceding text:

   ... There may be more than one matrix associated with
   a node as the node can partition the switch matrix into several sub-
   matrices for various reasons such as incremental updates, etc. When
   the matrix is partitioned into sub-matrices, it is envisioned that
   they are mutually exclusive to one another in representing which
   ports/labels are associated with each sub-matrix. This implies that
   two matrices will not have the same {src port, src label, dst port,
   dst label}.

I'd suggest directly addressing the ambiguity by revising the first
sentence and "for various reasons such as incremental updates, etc. " in
particular.  Perhaps "primarily to limit the size of any individual
information element used to represent the matrix."  or however else
you'd like to capture the intent.

Lou

On 2/2/2015 5:15 PM, Leeyoung wrote:
> Hi Lou,
>
> The original question Tomonori raised was if sub-matrices are like virtual nodes attached to connectivity matrix. The answer was no, and sub-matrix is simply a partition of connectivity matrix into smaller pieces. To that end, I added the following text in Section 2.1
>
>    Each sub-matrix is assigned a unique Matrix ID to represent a 
>    mutually exclusive set of {src port, src label, dst port, dst label} 
>    from other sub-matrices. 
>
> Let me know what you think.
>
> Thanks,
> Young
>
> -----Original Message-----
> From: Lou Berger [mailto:[e-mail]] 
> Sent: Monday, February 02, 2015 3:29 PM
> To: Leeyoung
> Cc: Tomonori Takeda; [e-mail]; '[e-mail]'; '[e-mail]'; '[e-mail]'
> Subject: Re: [RTG-DIR] RtgDir review: draft-ietf-ccamp-general-constraint-encode-16.txt
>
> Hi Young,
>
> I see you just published an update.  I have one question below.
>
> On 1/23/2015 3:01 AM, Tomonori Takeda wrote:
>> Hi Young,
>>
>> OK, thanks,
>>
>> Tomonori
>>
>> -----Original Message-----
>> From: Leeyoung [mailto:[e-mail]] 
>> Sent: Thursday, January 22, 2015 2:44 AM
>> To: Tomonori Takeda（武田知典）; Leeyoung; [e-mail]
>> Cc: '[e-mail]'; '[e-mail]'; '[e-mail]'
>> Subject: RE: [RTG-DIR] RtgDir review: draft-ietf-ccamp-general-constraint-encode-16.txt
>>
>> Hi Tomonori,
>>
>> Thanks for your comment. Please see in-line for my response. Please let me know if the response would satisfy you. 
>>
>> Best regards,
>> Young
>>
>> -----Original Message-----
>> From: Tomonori Takeda [mailto:[e-mail]] 
>> Sent: Wednesday, January 21, 2015 12:48 AM
>> To: Leeyoung; [e-mail]
>> Cc: '[e-mail]'; '[e-mail]'; '[e-mail]'; Tomonori Takeda
>> Subject: RE: [RTG-DIR] RtgDir review: draft-ietf-ccamp-general-constraint-encode-16.txt
>>
>> Hi Young,
>>
>> Thanks.
>>
>> Two follow-up questions/comments.
>> (I am fine with other points, which you already addressed in the updated draft.)
>>
>>> 2) In section 2.1, it says "two matrices will not have the same {src port, src label, dst port, dst label}". To be precise, I guess this should be > "two matrices will not have the same {src port, src label}, and two matrices will not have the same {dst port, dst label}"?
>>>
>>> YOUNG>> I think your suggestion may be too restrictive. For instance, if we have one source (port 1) and one destination (port 2) with two labels > each. Then we would have: {(1,1,2,1), (1,1,2,2), (1,2,2,1), (1,2,2,2)} I think with the current statement, we can send this info in any combination > of multiple matrices, which I think perfectly fine. With your suggestion, I would not be able send (1,1,2,1) and (1,1,2,2) together. Why would this > not be made possible? My take is as long as each submatrix represents a set of disjoint quadruples, that should be allowed.
>> My reading of "two matrices will not have the same {src port, src label, dst port, dst label}" is as follows.
>>
>> <Example A>
>>
>>   input port=1  --> Submatrix#1 --> output port=2
>>   input label=1                     output label=1
>>
>>   input port=1  --> Submatrix#2 --> output port=2
>>   input label=1                     output label=2
>>
>>   This is allowed.
>>
>> <Example B>
>>
>>   input port=1  --> Submatrix#1 --> output port=2
>>   input label=1                     output label=1
>>
>>   input port=1  --> Submatrix#2 --> output port=2
>>   input label=1                     output label=1
>>
>>   This is not allowed.
>>
>> <Example C>
>>
>>   input port=1  --> Submatrix#1 --> output port=2
>>   input label=1                     output label=1
>>
>>   input port=1  --> Submatrix#2 --> output port=2
>>   input label=2                     output label=2
>>
>>   This is allowed.
>>
>> Is above understanding correct?
>> If so, I am not sure how example A works, since I am not sure what is the indentifier to direct from input to each submatrix.
>>
>> Maybe I am mis-understanding what sub-matrix is. I thought sub-matrix is a sort of virtual node, splitting the single matrix (or switch) into smaller pieces.
> Can you explain how the revised text clarifies this point?
>
> Thanks,
> Lou
>
>> ....