Sdp Support In Megaco - AudioCodes Mediant 2000 User Manual

for this feature, is the VoIP metrics report block (Block 7). This block provides metrics
for monitoring VoIP calls.
The MEGACO ITU standard H.248.30 defines two packages to configure the RTCP-
XR and report the statistics: RTCPXR and XRBM.
MEGACO controls the activation of the RTCP-XR statistics calculation and reports the
statistics gathered by it. In addition, the activation of RTCP-XR statistics calculation
can be carried out by ini file parameter configuration.
7.2.3.1 Activation
If the Feature key allows for it, a call is marked to return RTCP-XR statistics, provided
that one or more of the following conditions is fulfilled:
MEGACO receives an ADD command in which there is an RTCP-XR in the
remote SDP with specification of block 7 (a=rtcp-xr: voip-metrics),
In the ini file RTCP-XR is set to ON
The localControl descriptor for this call contained a reference for the RTCP-XR
packages. It activates the Voice Engines API for collecting statistics, (if not
already active).
7.2.3.2 Deactivation
The MEGACO deactivates sending RTCP-XR packets if it gets a remote SDP with an
empty RTCP-XR attribute. (a=rtcp-xr: )
7.2.3.3 Statistics Report
The statistics for RTCP-XR is reported if the following conditions exist:
The lower level (Voice Engines) received statistics.
The call is marked for returning RTCP-XR statistics.
The report is issued when the call manager requests statistics, usually when closing a
call (Subtract), but also during the call (Audit).
7.2.4

SDP Support in MEGACO

MEGACO supports basic SDP, as defined in RFC 2327. It also supports SDP-ATM,
as defined in RFC 3108. The SDP parser can receive all lines defined in the RFC, but
it ignores all but the following lines: 'v', 'c', 'm', 'a'.
In addition to the above four lines, the outgoing SDP can contain the 't' 's' 'o' lines,
which are mandatory in some non-MEGACO applications. This option is controlled by
the ini file parameter MGCPCompatibilityProfile, by adding the number 8 to the
current value (2). For the SDP to have these lines, set the ini file parameter to 10.
In the 'a' line, the general supported attributes in SDP are:
SILENCESUPP:VAL
(VAL=on or off) - To turn silence suppression on or off (defined in RFC 3108)
RTPMAP
User's Manual 130
Mediant 2000
Document # LTRT-69805