Subject: payload type

From: Francisco Afonso <[email-masked]>
Date: Sun, 29 Aug 1999 00:14:49 -0700

About RTP...

What payload type values (PT) can I use for experimental work with other
time-based media ?

Francisco Afonso
Naval Postgraduate School.

---

From: Colin Perkins <[email-masked]>
Date: Sun, 29 Aug 1999 16:44:49 +0100

>What payload type values (PT) can I use for experimental work with other

Those in the range 96-127, which is for dynamic assignment. See rfc1890,
section 3.

Colin

---

From: Don Brutzman <[email-masked]>
Date: Sun, 29 Aug 1999 21:56:00 -0700

[added cc: dis-java-vrml group]

> Those in the range 96-127, which is for dynamic assignment. See rfc1890,

thanks Colin.  we are about to experiment with rtp headers for IEEE 
Distributed Interactive Simulation (DIS) protocol.

http://www.ietf.org/rfc/rfc1890.txt gives criteria for registering payload
types with IANA.  i expect we'll want to do that, presumably via an
internet draft, but first we're hoping to experiment without clobbering 
anyone else's experiments.

http://www.isi.edu/in-notes/iana/assignments/rtp-parameters
list current payload type assignments.  many of the numbers 
are "reserved" without further elaboration.

wondering if we should just pick and announce one on this mail list?
absent further guidance or objections, we'll use 111.

all the best, Don
-- 
Don Brutzman  Naval Postgraduate School, Code UW/Br Root 200  work 831.656.2149
              Monterey California 93943-5000 USA              fax  831.656.3679
Virtual worlds/underwater robots/Internet     http://web.nps.navy.mil/~brutzman

---

From: Colin Perkins <[email-masked]>
Date: Tue, 31 Aug 1999 12:02:26 +0100

>absent further guidance or objections, we'll use 111.

The payload type numbers in the dynamic assignment range do not need to be
registered. The intention is that they are negotiated using an out-of-band
signalling protocol, such as SAP, SIP or H.323, via the a=rtpmap attributes
in SDP. For example

	m=audio 26830 RTP/AVP 111
	a=rtpmap:111 L8/22050/2

or, including format specific parameters

	m=audio 47000 RTP/AVP 121
	a=rtpmap:121 red/8000/1
	a=fmtp:121 0/5

Your payload format needs a name (L8 and red in the examples) which will
(eventually) be registered in the MIME namespace if this becomes a standard, 
and should be prefixed "x-" during experiments. 

Colin