Subject: [lisp] #18: record count >1 for map request

From: "lisp issue tracker" <[email-masked]>
Date: Mon, 07 Sep 2009 22:57:42 -0000

#18: record count >1  for map request
----------------------------------+-----------------------------------------
Reporter:  [email-masked]  |       Owner:  [email-masked] 
    Type:  technical              |      Status:  new            
Priority:  major                  |   Component:  draft-ietf-lisp
Severity:  -                      |    Keywords:                 
----------------------------------+-----------------------------------------
 Dino> * How do deal with record count greater than 1 for a
     Dino> Map-Request.  Damien and Joel comment. Joel suggests:

     Dino>     1) Specify that senders compliant with the current
     Dino> document will always set the count to 1, and note that the
     Dino> count is included for future extensibility.

     Dino>     2) Specify what a receiver compliant with the draft
     Dino> should do if it receives a request with a count greater than
     Dino> 1. Presumably, it should send some error back?

 From the proposed lisp 04 text
    Record Count:  The number of records in this request message.  A
       record is comprised of the portion of the packet that is labeled
       'Rec' above and occurs the number of times equal to Record count.
       For this version of the protocol specification, a receiver MUST
       accept and process a record count of one or greater but a sender
       MUST always set the record count to one.

 As I understand it, this issue was opened exactly because we didn't
 know what a receiver should do with a record count is greater than 1.
 In any case, Dino's proposed text is inconistent with Joel's proposal
 so Dino and Joel need to touch base and come back to the WG with an
 explanation.

-- 
Ticket URL: <https://svn.tools.ietf.org/wg/lisp/trac/ticket/18>
lisp <http://tools.ietf.org/lisp/>
LISP WG document issues

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From: "Joel M. Halpern" <[email-masked]>
Date: Mon, 07 Sep 2009 19:59:52 -0400

After exchanging a few emails with Dino, I can think what is in the 
draft is sufficient to address the issue.

Yours,
Joel

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From: Dino Farinacci <[email-masked]>
Date: Mon, 7 Sep 2009 17:03:24 -0700

> draft is sufficient to address the issue.

Thanks Joel for clearing things up.

Dino

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From: Sam Hartman <[email-masked]>
Date: Mon, 07 Sep 2009 20:20:14 -0400

>>>>> "Joel" == Joel M Halpern <[email-masked]> writes:

    Joel> After exchanging a few emails with Dino, I can think what is
    Joel> in the draft is sufficient to address the issue.

OK, if no one objects by Friday we're done with this issue.

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From: Margaret Wasserman <[email-masked]>
Date: Mon, 7 Sep 2009 20:42:33 -0400

>       MUST always set the record count to one.

This text still doesn't say what a receiver should do if receives a  
record count greater than 1...

Should it throw the packet away?

Should it assume that there is only one record, and proceed accordingly?

Should it assume that there are N records in the packet (as indicated  
in the Record Count), but only process the first one?

Should it do something with multiple records?  If so, what?

Margaret

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From: "Joel M. Halpern" <[email-masked]>
Date: Mon, 07 Sep 2009 21:05:07 -0400

Actually, I read this as saying it (the receivers who receives a record 
count greater than 1) should simply process all of the records )
receive and process") which seems sufficient to me.

Joel

Margaret Wasserman wrote:
> Should it assume that there are N records in the packet (as indicated in 
> the Record Count), but only process the first one?
> 
> _______________________________________________
> lisp mailing list
> [email-masked]
> https://www.ietf.org/mailman/listinfo/lisp
>

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From: Dino Farinacci <[email-masked]>
Date: Mon, 7 Sep 2009 19:25:30 -0700

> record count greater than 1...

Right, because the text in processing a Map-Request says what to do.  
This section is just describing the Record Count field and not the  
entire protocol.

> Should it throw the packet away?

"MUST accept" above should tell you it means to not throw it away.

> Should it assume that there is only one record, and proceed  

"a record count of one or greater" above should tell you that the  
receiver should expect more than one record.

> Should it assume that there are N records in the packet (as  
> indicated in the Record Count), but only process the first one?

No, why would you think that. The text never said that so don't assume  
anything else.

Dino

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From: Margaret Wasserman <[email-masked]>
Date: Tue, 8 Sep 2009 09:33:31 -0400

Hi Dino,

>>>     MUST always set the record count to one.

This would be clearer to me if you changed the last sentence to read:

"For this version of the protocol, a receiver MUST accept and process  
requests that contain one or more records, but a sender MUST only send  
requests containing one record."

Margaret

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From: Dino Farinacci <[email-masked]>
Date: Tue, 8 Sep 2009 07:30:36 -0700

> "For this version of the protocol, a receiver MUST accept and  
> process requests that contain one or more records, but a sender MUST  
> only send requests containing one record."
>
> Margaret

So you just deleted the word "specification", and added "request" a  
couple of times. Is that your intent?

What about the last sentence:

"Support for requesting multiple EIDs in a single Map-Request message  
will be specified in a future version    of the protocol."

I think we should keep it. Please confirm.

Dino

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From: Dino Farinacci <[email-masked]>
Date: Tue, 8 Sep 2009 07:35:17 -0700

This this text satisfactory?

    Record Count:  The number of records in this Map-Request message.  A
       record is comprised of the portion of the packet that is labeled
       'Rec' above and occurs the number of times equal to Record Count.
       For this version of the protocol, a receiver MUST accept and
       process Map-Requests that contain one or more records, but a
       sender MUST only send Map-Requests containing one record.   
Support
       for requesting multiple EIDs in a single Map-Request message will
       be specified in a future version of the protocol.

Dino

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From: Margaret Wasserman <[email-masked]>
Date: Tue, 8 Sep 2009 11:14:46 -0400

That looks good, Dino.  Thanks!

Margaret

On Sep 8, 2009, at 10:35 AM, Dino Farinacci wrote:

>> process requests that contain one or more records, but a sender  
>> MUST only send requests containing one record."
>>
>> Margaret
>

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From: Dino Farinacci <[email-masked]>
Date: Tue, 8 Sep 2009 08:16:12 -0700

Thanks for the quick reply. I'll send a new diff file by end of day.  
Just so I can capture other comments I think I'll get throughout today.

Dino