Re: [sipcore] draft-ietf-sipcore-keep - Peter's comments

[Christer Holmberg <[e-mail]>]

Hi, 

>>>4.4 para 2. This paragraph is one sentence. I read it many times - I 
>>>gave up.
>>
>>I tried to make the paragraph more readable. It still 
>>contain a long sentence, but please let me know if it's 
>>easier to understand now:
>>
>>        "When a SIP entity creates or receives a response, and the 
>>        adjacent downstream SIP entity that sent the associated request 
>>        indicated willingness to send keep-alives, if the SIP entity 
>>        is willing to receive keep-alives associated with the registration 
>>        (in case of a REGISTER response), or the dialog (in case of a 
>>        response to an initial request for a dialog, or a response to a mid-dialog
>>        target refresh request), from the adjacent downstream SIP entity it MUST 
>>        add a parameter value to the "keep" parameter, before sending
>>        or forwarding the response. The parameter can contain a recommended keep-alive 
>>        frequency, or a zero value."
>>
>Better - but I am still getting a stack overflow since I parse "When... A or B ..and...if..or.."

You should take a look at some 3GPP specifications :)

>How about:
> 
>If a request from a downstream SIP element indicated support 
>for keep-alives and the upstream element also supports 
>keep-alives then the response from the upstream element MUST 
>contain a parameter value for the "keep". This value can 
>contain a recommended keep-alive value or a zero value.
> 
>(I have cut out the stuff on what kind of request it is - I 
>am not sure if this distinction was vital?)

I think it is important to indicate the "scope" (registration or dialog) for which the entity
Indicates willingess to receive keep-alives.

I guess the "in case of..." parts could be removed.

Also, the "the response from the upstream element" is a little confusing, because it seems to refer to some other entity (the "reference point" in the text is the SIP entity that inserts the value in the keep header). I would like to use "the SIP entity", as elsewhere in the document.

Regards,

Christer