Subject: [AVT] I-D ACTION:draft-ietf-avt-app-rtp-keepalive-02.txt

From: [email-masked]
Date: Fri, 8 Feb 2008 14:30:01 -0800 (PST)

A New Internet-Draft is available from the on-line Internet-Drafts 
directories.
This draft is a work item of the Audio/Video Transport Working Group of the IETF.

	Title		: Application Mechanism for maintaining alive the Network Address Translator (NAT) mappings associated to RTP flows.
	Author(s)	: X. Marjou, A. Sollaud
	Filename	: draft-ietf-avt-app-rtp-keepalive-02.txt
	Pages		: 11
	Date		: 2008-2-8
	
This document lists the different mechanisms that enable applications
   using Real-time Transport Protocol (RTP) to maintain their RTP
   Network Address Translator (NAT) mappings alive.  It also makes a
   recommendation for a preferred mechanism.  This document is not
   applicable to Interactive Connectivity Establishment (ICE) agents.

A URL for this Internet-Draft is:
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---

From: Colin Perkins <[email-masked]>
Date: Sun, 10 Feb 2008 10:48:33 +0000

On 8 Feb 2008, at 22:30, [email-masked] wrote:
> 	Title		: Application Mechanism for maintaining alive the Network  
> Address Translator (NAT) mappings associated to RTP flows.

The changes in this revision look generally very good. Two minor  
comments:

- Rather than make a special case for T.140 text using a different  
fallback keep-alive mechanism than other payload formats, should the  
draft recommend that payload format specific mechanisms should  
generally be used in multiplexed RTCP cannot? Empty T.140 blocks  
would be one example of this, as would comfort noise, etc.

- Section 6 should discuss how the interval Tr relates to the RTCP  
timing rules.

-- 
Colin Perkins
http://csperkins.org/

---

From: Gunnar Hellström <[email-masked]>
Date: Sat, 9 Feb 2008 23:49:35 +0100

The updated keepalive draft looks good and concise and has a straightforward
recommendation.

And now it also gives a good specific alternative for RFC 4103 traffic, for
cases when the main recommended way is not possible. Good.

A small thing: There is still a reference to draft-ietf-avt-no-op. That
draft has expired and is not available anymore, and thus not possible to
reference. So, section 4.6 needs to be deleted or that draft revived.

Gunnar

-------------------------------------------------------------------
Gunnar Hellström
Omnitor
[email-masked]
Tel: +46708204288
www.omnitor.se

A New Internet-Draft is available from the on-line Internet-Drafts
directories.
This draft is a work item of the Audio/Video Transport Working Group of the
IETF.

	Title		: Application Mechanism for maintaining alive the
Network Address Translator (NAT) mappings associated to RTP flows.
	Author(s)	: X. Marjou, A. Sollaud
	Filename	: draft-ietf-avt-app-rtp-keepalive-02.txt
	Pages		: 11
	Date		: 2008-2-8

---

From: "Jaehwan Kim" <[email-masked]>
Date: Mon, 11 Feb 2008 09:06:27 +0900

Hello,
Although avt-no-op is expired, I think such a guideline is good.
Most of off-the-shelf mobile players seem to send it or null UDP packet.

Therefore, I recommend keeping it at least until this draft is finalized. 

Regards,
Jaehwan

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of Gunnar Hellstrom
Sent: Sunday, February 10, 2008 7:50 AM
To: [email-masked]
Subject: Re: [AVT] I-D ACTION:draft-ietf-avt-app-rtp-keepalive-02.txt

Gunnar

---

From: "Jaehwan Kim" <[email-masked]>
Date: Mon, 11 Feb 2008 12:43:55 +0900

Correction:
'Players using no-op is not most of them. Most of them use "4.8.  RTP Packet with Unknown Payload Type" but some uses no-op although they don't use MIME for SDP.'

The problem is that there is not much information for NAT traversal. 
Each vendor made their own format. That no-op was one of solutions and that's why they use it according to them. (Null UDP packet was one but no discussion except question regarding DCCP. But there seems a patent issue for this solution)

Anyway, we got many questions and IOT issues for this in the field.
Therefore, any rule must be made ASAP.

Regards,
Jaehwan

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of Jaehwan Kim
Sent: Monday, February 11, 2008 9:06 AM
To: Gunnar Hellström; [email-masked]
Subject: Re: [AVT] I-D ACTION:draft-ietf-avt-app-rtp-keepalive-02.txt

Hello,

Regards,
Jaehwan

-----Original Message-----
From: [email-masked] [mailto:[email-masked]] On Behalf Of Gunnar Hellstrom
Sent: Sunday, February 10, 2008 7:50 AM
To: [email-masked]
Subject: Re: [AVT] I-D ACTION:draft-ietf-avt-app-rtp-keepalive-02.txt

Gunnar