Support Of Asymmetric Tx/Rx Payloads; Rfc 3407 Support – Simple Capabilities - AudioCodes Mediant 2000 User Manual

m=audio $ $ $
a=ptime:$
The reply is a list of all supported coders.
7.2.4.2.1

Support of Asymmetric Tx/Rx Payloads

In the MEGACO commands, up to two SDP sessions are received. One SDP session
for the local side and the another SDP session for the remote side. Each SDP can
contain a different definition of the payloads to be used for the same coder. In the
reply the result of the negotiation between the local SDP and remote SDP is returned.
The reply contains the negotiated coder, and the payload type to be used is included
in the SDP session from the local side (not the SDP session from the remote side). As
a result, the media stream SENT FROM the board uses the payload received in the
remote SDP, but the media stream RECEIVED IN the board is to use the payload type
defined in the local SDP.
7.2.4.3 RFC 3407 Support – Simple Capabilities
RCF 3407 defines a minimal and backward-compatible capability declaration feature
in SDP by defining a set of new SDP attributes. Together, these attributes define a
capability set, which consists of a capability set sequence number followed by one or
more capability descriptions.
information about supported media formats, but the endpoint is not required to use
any of these. In order to actually use a declared capability, session negotiation must
be carried out by the call manager.
Example 1
The following call flows example illustrates the usage of this capability:
MEGACO/1 [10.2.1.228]:2944
Transaction = 10264 {
Context = $ {
Local {
v=0
c=IN IP4 $
m=audio $ RTP/AVP 0
m=image $ UDPTL t38
},
Remote {
v=0
c=IN IP4 10.4.4.46
m=audio 4020 RTP/AVP 0
}}}}}
The reply to this is:
MEGACO/1 [10.4.4.46]:2944
P=10264{
C=2{
A = gwRTP/1{
M{
L{
User's Manual
Add = $ {Media {
LocalControl {
Mode = Receiveonly
},
Each capability description in the set contains
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Mediant 2000
Document # LTRT-69805