Re: [bfcpbis] Comments on draft-ietf-bfcpbis-rfc4582bis-04

[Tom Kristensen <[e-mail]>]

On 07/16/2012 02:51 PM, Alfred E. Heggestad wrote:
> Hi,
>
>
> here is my review comments of draft-ietf-bfcpbis-rfc4582bis-04

Great! (I'll split my answers in separate messages per subsection)

>  > Section 5.1
>  >
>> R: The Transaction Responder (R) flag-bit has relevance only for use
>> of BFCP over unreliable transport. When cleared, it indicates that
>> this message is a request initiating a new transaction, and the
>> Transaction ID that follows has been generated for this transaction.
>> When set, it indicates that this message is a response to a previous
>> request, and the Transaction ID that follows is the one associated
>> with that request. When BFCP is used over reliable transports, the
>> flag has no significance and SHOULD be cleared.
>
> suggest rewrite to .. "SHALL be cleared by the sender and ignored by
> the receiver"

If I recall correctly, the SHOULD is used since both the Fragmentation 
(F) flag bit and the Transaction Responder (R) flag bit is taken from 
the 5 bit reserved field in RFC4582. When used over reliable transport 
(and version==1), we'd like be backwards compatible and not mandate 
setting these bits to zero. (Even though the sender SHOULD indeed, and 
the receiver MUST ignore the reserved field).

However, I agree that we should append "...[SHOULD be cleared] by the 
sender of the message and MUST be ignored by the receiver" to this 
sentence in question for both the R and F fields.

OK?

-- Tom