Wireshark-bugs: [Wireshark-bugs] [Bug 5208] RTP dynamic payload type can not be dissected correc
https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=5208
qiangxiong.huang@xxxxxxxxx changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|RESOLVED |REOPENED
Resolution|INVALID |
--- Comment #4 from qiangxiong.huang@xxxxxxxxx 2010-09-14 07:09:27 PDT ---
(In reply to comment #3)
> The problem is:
> :
> Connection Information (c): IN IP4 0.0.0.0
> :
> Media Description, name and address (m): audio 0 RTP/AVP 97
> e.g no adress or port information is given in the SDP for Wireshark
> to make a "conversation" where SDP data can be matched to the RTP packet.
> Regards
> Anders
The situation that zero address (c=IN IP4 0.0.0.0) and zero port (m=audio 0
RTP/AVP 97) is normal and valid in RTSP's SDP.
Not like SIP session that the RTP media receiver's address and port are given
in SDP, RTSP's SDP is normally send from media sender to receiver. Normally RTP
receiver does not send SDP to sender.
So wireshark should get address/port from RTSP's "Transport" header instead of
from SDP's "c=" and "m=" lines.
The correct method is:
(1) Get the RTP receiver port from "Transport" header's "client_port", "port"
or "interleaved" parameters;
(2) Get the RTP receiver ip address from "Transport" header's "destination" if
"destination" is present, else take RTSP's client ip as RTP receiver ip
directly.
Following content is coming from RFC2326 (Appendix C: Use of SDP for RTSP
Session Descriptions):
------About zero port in SDP "m=" line-------------:
C.1.2 Media streams
The "m=" field is used to enumerate the streams. It is expected that
all the specified streams will be rendered with appropriate
synchronization. If the session is unicast, the port number serves as
a recommendation from the server to the client; the client still has
to include it in its SETUP request and may ignore this
recommendation. If the server has no preference, it SHOULD set the
port number value to zero.
Example:
m=audio 0 RTP/AVP 31
------About zero ip in SDP "c=" line-------------:
C.1.7 Connection Information
In SDP, the "c=" field contains the destination address for the media
stream. However, for on-demand unicast streams and some multicast
streams, the destination address is specified by the client via the
SETUP request. Unless the media content has a fixed destination
address, the "c=" field is to be set to a suitable null value. For
addresses of type "IP4", this value is "0.0.0.0".
--
Configure bugmail: https://bugs.wireshark.org/bugzilla/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.
