AudioCodes Mediant 500 MSBR, User Manual

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Version 7.2 415 Mediant 500 MSBR
User's Manual 23. Coders and Profiles
Parameter Description

[1] Original Offer = Use ptime according to SDP offer.

[2] Preferred Value= Use preferred ptime for negotiation, if
configured by the 'Preferred Ptime' parameter.
Preferred Ptime
sbc-preferred-ptime
[IpProfile_SBCPreferredPTime]
Defines the packetization time (in msec) for the SIP entity
associated with the IP Profile if the 'SBC SDP Ptime Answer'
parameter (see above) is set to Preferred Value.
The valid range is 0 to 200. The default is 0 (i.e., preferred ptime
is not used).
Use Silence Suppression
sbc-use-silence-supp
[IpProfile_SBCUseSilenceSupp]
Defines silence suppression support for the SIP entity associated
with the IP Profile

[0] Transparent = (Default) Forward as is.

[1] Add = Enable silence suppression for each relevant coder
listed in the SDP.

[2] Remove = Disable silence suppression for each relevant
coder listed in the SDP.
Note: The parameter requires DSP resources.
RTP Redundancy Mode
sbc-rtp-red-behav
[IpProfile_SBCRTPRedundancyB
ehavior]
Enables interworking RTP redundancy negotiation support
between SIP entities in the SDP offer-answer exchange
(according to RFC 2198). The parameter defines the device's
handling of RTP redundancy for the SIP entity associated with
the IP Profile. According to the RTP redundancy SDP
offer/answer negotiation, the device uses or discards the RTP
redundancy packets. The parameter enables asymmetric RTP
redundancy, whereby the device can transmit and receive RTP
redundancy packets to and from a specific SIP entity, while
transmitting and receiving regular RTP packets (no redundancy)
for the other SIP entity involved in the voice path.
The device can identify the RTP redundancy payload type in the
SDP for indicating that the RTP packet stream includes
redundant packets. RTP redundancy is indicated in SDP using
the "red" coder type, for example:
a=rtpmap:<payload type> red/8000/1
RTP redundancy is useful when there is packet loss; the missing
information may be reconstructed at the receiver side from the
redundant packets.

[0] As Is = (Default) The device does not interfere in the RTP
redundancy negotiation and forwards the SDP offer/answer
(incoming and outgoing calls) as is without interfering in the
RTP redundancy negotiation.

[1] Enable = The device always adds RTP redundancy
capabilities in the outgoing SDP offer sent to the SIP entity.
Whether RTP redundancy is implemented depends on the
subsequent incoming SDP answer from the SIP entity. The
device does not modify the incoming SDP offer received from
the SIP entity, but if RTP redundancy is required, it will be
supported. Select the option if the SIP entity requires RTP
redundancy.

[2] Disable = The device removes the RTP redundancy
payload (if present) from the SDP offer/answer for calls
received from or sent to the SIP entity. Select the option if the