Re: [Sipping] draft-york-sipping-p-charge-info-12: ABNF

["Asveren, Tolga" <[e-mail]>]

Brett,

 

The answer for your question is "both", at least that was the intention.

 

Thanks,

Tolga

 

From: Haluska, John J [mailto:[e-mail]] 
Sent: Wednesday, November 30, 2011 8:11 AM
To: Dan York; Brett Tate
Cc: Asveren, Tolga; [e-mail]
Subject: RE: draft-york-sipping-p-charge-info-12: ABNF

 

Dan,

 

I'll take a look and let you know - I'm out of MIPS at the moment.

 

Thanks for continuing with this even though you've moved on.

 

 

John

 

 

 

From: Dan York [mailto:[e-mail]] 
Sent: Tuesday, November 29, 2011 2:38 PM
To: Brett Tate
Cc: Tolga Asveren; [e-mail]; Haluska, John J
Subject: Re: draft-york-sipping-p-charge-info-12: ABNF

 

Brett, (and replying from a slightly different address so that it will
go to the SIPPING list)

 

Thank you for the feedback and question.  The ABNF in the draft has
evolved over the past almost-4 years as various people more literate
than I in ABNF have given us feedback and we've updated the draft.

 

In the ABNF section, "chargeparam" is intended to represent that you
could optionally have the "noa", "npi" parameters - or any other generic
parameters found in RFC 3261(such as "user=phone")

 

Originally, the ABNF read:

 

         P-Charge-Info = "P-Charge-Info" HCOLON (name-addr / addr-spec)*
                 (SEMI charge-param)
                 ; name-addr and addr-spec are specified in RFC 3261
<http://tools.ietf.org/html/rfc3261> 
             charge-param = npi-param / noa-param / generic-param

 

I thought that was fairly clear and made sense.  However, I changed the
ABNF in rev -10 in October 2010 to more simply:

 

         P-Charge-Info = "P-Charge-Info" HCOLON (name-addr / addr-spec)
                 ; name-addr and addr-spec are specified in RFC 3261
<http://tools.ietf.org/html/rfc3261> 
             charge-param = npi-param / noa-param / generic-param

 

after someone strongly made the case that the "* (SEMI charge-param)"
was not required because it was a "userinfo parameter" to the
name-addr/addr-spec element.  Unfortunately, the email exchange about
this seems to have NOT taken place on the mailing list but rather in a
private email exchange - and I no longer have access to the archives of
the email account where that occurred (I am no longer with Voxeo) - so I
don't know who it was that argued for this change.

 

I'm directly cc'ing John Haluska as he was involved in with a number of
those exchanges and can perhaps clarify this.

 

In reviewing section 19.1.1 of RFC 3261 (
http://tools.ietf.org/html/rfc3261#section-19.1.1 ) and sections 19.1.2,
19.1.3, and 19.1.6 as well as the ABNF in section 25,  I am guessing
that the rationale was because the "charge-param" does fit into the
"user" section of the URI.

 

So that's a roundabout way of saying that it is part of "user", as I
interpret the ABNF in RFC 3261.

 

Do you have suggestions for how to make this clearer in the draft?
Would the original ABNF be more useful to you?  Should the sentence
"charge-param is used as a userinfo parameter in P-Charge-Info" indicate
that it is the "user" part of the "userinfo" field?

 

Thanks,

Dan

 

P.S. After not receiving any feedback for many, many months I suddenly
have received two email questions/comments about P-Charge-Info today. I
don't know if this is as a result of the mention on a mailing list that
Richard Shockey mentioned... but I was surprised. 

 

On Nov 29, 2011, at 1:35 PM, Brett Tate wrote:

 

Howdy,

Draft-york-sipping-p-charge-info-12 includes the following ABNF without
explicitly indicating if the charge-param is part of user,
telephone-subscriber, or both.  I'm not sure how to interpret the
charge-param statement since userinfo has no parameters (although user
and telephone-subscriber can have them).

Is charge-param part of user, telephone-subscriber, or both?  I
recommend updating section 7 to remove the ambiguity.

Thanks,
Brett


------

Draft-york-sipping-p-charge-info-12:

"The syntax of the P-Charge-Info header is described as follows:

        P-Charge-Info = "P-Charge-Info" HCOLON (name-addr / addr-spec)
                ; name-addr and addr-spec are specified in RFC 3261
            charge-param = npi-param / noa-param / generic-param
            npi-param = ";npi" EQUAL npi-value
                ; generic-param is specifed in RFC 3261
            npi-value = gen-value
            noa-param = ";noa" EQUAL noa-value
            noa-value = gen-value

  The SIP URI contained in the name-addr/addr-spec is the billing
  indicator that is passed between the parties.

  charge-param is used as a userinfo parameter in P-Charge-Info."


RFC 3261:

userinfo =  ( user / telephone-subscriber ) [ ":" password ] "@"
user     =  1*( unreserved / escaped / user-unreserved )

RFC 2806:

telephone-subscriber  = global-phone-number / local-phone-number

 

-- 
Dan York  [e-mail]

Phone: [phone]  skype:danyork
http://www.danyork.com/  
http://twitter.com/danyork

 

 

-- 
Dan York  [e-mail]
http://www.danyork.com/   skype:danyork
Phone: [phone]
Twitter - http://twitter.com/danyork

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