Early Media; 180 Ring Workaround - Yealink SIP-T2 SERIES Administrator's Manual

Administrator's Guide for SIP-T2 Series/T19(P) E2/T4 Series/CP860 IP Phones

Early Media

Early media refers to media (e.g., audio and video) played to the caller before a SIP call is
actually established. Current implementation supports early media through the 183 message.
When the caller receives a 183 message with SDP before the call is established, a media channel
is established. This channel is used to provide the early media stream for the caller.

180 Ring Workaround

180 ring workaround defines whether to deal with the 180 message received after the 183
message. When the caller receives a 183 message, it suppresses any local ringback tone and
begins to play the media received. 180 ring workaround allows IP phones to resume and play
the local ringback tone upon a subsequent 180 message received.
Procedure
180 ring workaround can be configured using the configuration files or locally.
Configuration File
Local
Details of the Configuration Parameter:
phone_setting.is_deal180
Description:
Enables or disables the IP phone to deal with the 180 SIP message received after the 183 SIP
344
<y0000000000xx>.cfg
Web User Interface
Parameter
Configure 180 ring workaround.
Parameter:
phone_setting.is_deal180
Configure 180 ring workaround.
Navigate to:
For
SIP-T48G/T46G/T42G/T41P/T40P/T2
9G/T27P/T23P/T23G/T21(P)
E2/T19(P) E2/CP860:
http://<phoneIPAddress>/servlet?p
=features-general&q=load
For SIP VP-T49G:
http://<phoneIPAddress>/servlet?m
=mod_data&p=features-general&q
=load
Permitted Values
0 or 1
Default
1