Re: [Sipping] Hi Paul //About draft-ietf-sipping-sip-offeranswer-11

["DRAGE, Keith (Keith)" <keith.drage@xxxxxxxxxxxxxxxxxx>]

offeranswer was the informational document that examined poor usage of existing normative specification text in RFC 3264. It is not intended to carry nomative information in its own right.

 

If you feel normative language is needed, then you need a document that updates RFC 3264, either as a separate document or one that replaces it. We have talked about that in the past as part of the SIP work, shortly before the SIP group got closed.

 

regards

 

Keith

---

From: sipping-bounces@xxxxxxxx [mailto:sipping-bounces@xxxxxxxx] On Behalf Of gao.yang2@xxxxxxxxxx
Sent: Tuesday, March 02, 2010 7:02 AM
To: Paul Kyzivat
Cc: sipping
Subject: Re: [Sipping] Hi Paul //About draft-ietf-sipping-sip-offeranswer-11

Hi Paul,

I just feel adding some BCP level description (something like the description below) would let people do system design and implement clearly.

"When recv Re-INVITE without Offer, UAS SHOULD avoid of introducing new media types without user's permission or local policy configuration, that is its current using media types."

Thanks,

Gao

===================================
Zip    : 210012
Tel    : 87211
Tel2   :(+86)-025-52877211
e_mail : gao.yang2@xxxxxxxxxx
===================================
----- 转发人 GaoYang140197/user/zte_ltd 时间 2010-03-02 14:56 -----

GaoYang140197/user/zte_ltd

2010-03-01 13:44

收件人	Paul Kyzivat <pkyzivat@xxxxxxxxx>
抄送	sipping <sipping@xxxxxxxx>
主题	Re: Hi Paul  //About draft-ietf-sipping-sip-offeranswer-11链接

As you have a new version, I think including sipping would be better :)

Thanks for your agreement at this point.

But as RFC3261's words of "willings" is not as clear as guidance for system design and implement, I think some BCP level description vcould be better.

Thanks,

Gao

===================================
Zip    : 210012
Tel    : 87211
Tel2   :(+86)-025-52877211
e_mail : gao.yang2@xxxxxxxxxx
===================================

Paul Kyzivat <pkyzivat@xxxxxxxxx>

2010-02-26 22:17

收件人	gao.yang2@xxxxxxxxxx
抄送	sipping <sipping@xxxxxxxx>
主题	Re: Hi Paul  //About draft-ietf-sipping-sip-offeranswer-11

gao.yang2@xxxxxxxxxx wrote:
>
> I just find a potential problem of
> draft-ietf-sipping-sip-offeranswer-11. I am not sure will you want have
> a new version, so I send this discussion offline.

I am working on another version. I am including sipping in my response
so others have the opportunity to comment. (I trust that is ok.)

> Section 5.2.5. of draft-ietf-sipping-sip-offeranswer-11:
> When the new offer is sent in response to an offerless (re)INVITE,
>    *all codecs supported by the UA are to be included*, not just the ones
>    that were negotiated by previous offer/answer exchanges.  *The same is*
> *   true for media types* - so if UA A initially offered audio and video
>    to UA B, and they end up with only audio, and UA B sends an offerless
>    (re)INVITE to UA A, A's resulting offer should re- attempt video, by
>    reusing the zeroed m-line used previously.
>
>
> While Re-INVITE without Offer:
> For codecs, I think the UAS should include as many codecs that the UA is
> willing(section 14.2 of RFC3261) to support. I think we should let the
> UA has the right to decide which codecs can be use or not for this
> current call. At the same time, the UAS should be with responsibility
> for failure of session if it cut down the number of codecs. UAS's
> willing of codecs can be implemented as local policy or some other forms
> of configuration.

Yes, this just requires minor tweak to wording.
Its consistent with the recommendations on sendonly/...

> For media types, it is almost the same as codecs, about UA's willing.
> But I think we should emphasize on avoiding of introducing new media
> types without user's permission, such as just introducing new media
> types  by equipment or software. Beacause I have met such charging
> arguement from users in some operating telecom-network.(If you want the
> detail of the charging arguement, I'd like to share it with you).
> So, if there is no indication of permission of introducing new media
> types from the end user, UAS should just include current using media
> types. And if the other side(user of UAC) want to add media types, it
> can using another new Offer.

I get your point and agree. Its the same concept - include everything
the UA would be willing to use, not just that which it thinks the peer
wants to use.

                Thanks,
                Paul

> Thanks,
>
> Gao
>
> Section 14.2 of RFC3261:
> A UAS providing an offer in a 2xx (because the INVITE did not contain
>    an offer) SHOULD construct the offer as if the UAS were making a
>    brand new call, subject to the constraints of sending an offer that
>    updates an existing session, as described in [13] in the case of SDP.
>    Specifically, this means that it SHOULD include as many media formats
>    and media types that the UA *is willing to support*.  The UAS MUST
>    ensure that the session description overlaps with its previous
>    session description in media formats, transports, or other parameters
>    that require support from the peer.  This is to avoid the need for
>    the peer to reject the session description.  
>
> ===================================
> Zip    : 210012
> Tel    : 87211
> Tel2   :(+86)-025-52877211
> e_mail : gao.yang2@xxxxxxxxxx
> ===================================
>
> --------------------------------------------------------
> ZTE Information Security Notice: The information contained in this mail is solely property of the sender's organization. This mail communication is confidential. Recipients named above are obligated to maintain secrecy and are not permitted to disclose the contents of this communication to others.
> This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the originator of the message. Any views expressed in this message are those of the individual sender.
> This message has been scanned for viruses and Spam by ZTE Anti-Spam system.
>

--------------------------------------------------------
ZTE Information Security Notice: The information contained in this mail is solely property of the sender's organization. This mail communication is confidential. Recipients named above are obligated to maintain secrecy and are not permitted to disclose the contents of this communication to others.
This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the originator of the message. Any views expressed in this message are those of the individual sender.
This message has been scanned for viruses and Spam by ZTE Anti-Spam system.

_______________________________________________
Sipping mailing list  https://www.ietf.org/mailman/listinfo/sipping
This list is for NEW development of the application of SIP
Use sip-implementors@xxxxxxxxxxxxxxx for questions on current sip
Use sip@xxxxxxxx for new developments of core SIP