AudioCodes Mediant 4000 SBC User Manual page 441

CHAPTER 19 Coders and Profiles
Parameter
'Adapt RFC2833 BW to Voice
coder BW'
sbc-adapt-rfc2833-bw-
voice-bw
[IpProfile_
SBCAdaptRFC2833BWToVoic
eCoderBW]
'SDP Ptime Answer'
sbc-sdp-ptime-ans
[IpProfile_
SBCSDPPtimeAnswer]
Description
■ When using the X-AC-Action header to switch IP
Profiles, it is recommended that the settings of the
switched IP Profile are identical (except for the 'Send
Multiple DTMF Methods' parameter) to the initial IP
Profile in order to avoid any possible call handling
errors.
■ The parameter is applicable only to the SBC
application.
Defines the 'telephone-event' type (8000 or 16000) in the
SDP that the device sends in the outgoing SIP 200 OK
message for DTMF payload negotiation (sampling rate).
■ [0] Disable = (Default) The device always sends the
'telephone-event' as 8000 in the outgoing SIP 200 OK,
even if the SDP of the incoming INVITE contains
multiple telephone-event types (e.g., 8000 and 16000).
■ [1] Enable = The type of 'telephone-event' that the
device sends in the outgoing SIP 200 OK message is
according to the coder type (narrowband or wideband).
If narrowband, it sends the 'telephone-event' as 8000; if
wideband, it sends it as 16000.
An example when the parameter is configured to Enable is
shown below, whereby the 'telephone-event' is "16000" in
the outgoing message due to the wideband coder:
SDP in incoming INVITE:
a=rtpmap:97 AMR-WB/16000/1 a=fmtp:97 mode-
change-capability=2 a=rtpmap:98 AMR-
WB/16000/1 a=fmtp:98 octet-align=1; mode-
change-capability=2 a=rtpmap:100
AMR/8000/1 a=fmtp:100 mode-change-
capability=2 a=rtpmap:99 telephone-
event/16000/1 a=fmtp:99 0-15 a=rtpmap:102
telephone-event/8000/1 a=fmtp:102 0-15
SDP in outgoing 200 OK:
m=audio 6370 RTP/AVP 97 99
a=rtpmap:99 telephone-event/16000/1
a=fmtp:99 0-15
a=sendrecv
a=ptime:20
a=maxptime:120
a=rtpmap:97 AMR-WB/16000
a=fmtp:97 mode-change-capability=2;mode-
set=0,1,2,3,4,5,6,7,
Defines the packetization time (ptime) of the coder in RTP
packets for the SIP entity associated with the IP Profile.
This is useful when implementing transrating.
■ [0] Remote Answer = (Default) Use ptime according to
SDP answer.
■ [1] Original Offer = Use ptime according to SDP offer.
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Mediant 4000 SBC | User's Manual