[SIPForum-discussion] SDP Format

[Garron, James]

Per RFC4566 I believe that your statement is correct:

 

An SDP session description consists of a session-level section followed
by zero or more media-level sections. The session-level part starts with
a "v=" line and continues to the first media-level section. Each
media-level section starts with an "m=" line and continues to the next
media-level section or end of the whole session description. In general,
session-level values are the default for all media unless overridden by
an equivalent media-level value. 

Some lines in each description are REQUIRED and some are OPTIONAL, but
all MUST appear in exactly the order given here (the fixed order greatly
enhances error detection and allows for a simple parser). OPTIONAL items
are marked with a "*". 

Session description 
v= (protocol version) 
o= (originator and session identifier) 
s= (session name) 
i=* (session information) 
u=* (URI of description) 
e=* (email address) 
p=* (phone number) 
c=* (connection information -- not required if included in all media) 
b=* (zero or more bandwidth information lines) 
One or more time descriptions ("t=" and "r=" lines; see below) z=* (time
zone adjustments) 
k=* (encryption key) 
a=* (zero or more session attribute lines) 
Zero or more media descriptions 

Time description 
t= (time the session is active) 
r=* (zero or more repeat times) 

Media description, if present 
m= (media name and transport address) 
i=* (media title) 
c=* (connection information -- optional if included at session level) 
b=* (zero or more bandwidth information lines) 
k=* (encryption key) 
a=* (zero or more media attribute lines) 

 

 

 

________________________________

From: discussion-bounces at sipforum.org
[mailto:discussion-bounces at sipforum.org] On Behalf Of Jyoti Parija
Sent: Thursday, July 09, 2009 1:48 PM
To: discussion at sipforum.org
Subject: [SIPForum-discussion] SDP Format

 

 

Hello,

 

Please let me know if the below is a valid SDP as per my knowledge I
think this is not correct because, each Media Block Must start and end
with all its corresponding attributes placed before the next Media
Section.  The "a=T38" is a particular Fax Map Notation expected after
the m=image line. 

 

m=image 17654 udptl t38

m=audio 17654 RTP/AVP 0 8 101 

a=T38FaxVersion:0 

a=rtpmap:101 telephone-event/8000 

a=fmtp:101 0-16 

a=ptime:20

 

Please correct me if I am wrong.

 

Thanks,

JP

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sipforum.org/pipermail/discussion/attachments/20090710/b2fa00c1/attachment-0002.html>