Yealink SIP-T2 SERIES Administrator's Manual page 477

When the RFC 4916 is enabled on the IP phone, the caller sends the SIP request
message which contains the from-change tag in the Supported header. The caller
then receives an UPDATE message from the callee, and displays the identity in the
―From‖ header.
X ranges from 1 to 16 (for SIP VP-T49G/SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860)
Web User Interface:
None
Phone User Interface:
None
account.X.cid_source_privacy
Description:
Enables or disables the IP phone to process Privacy header field in the SIP message
for account X.
0-Disabled
1-Enabled
X ranges from 1 to 16 (for SIP VP-T49G/SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860)
Web User Interface:
None
Phone User Interface:
None
DTMF (Dual Tone Multi-frequency), better known as touch-tone, is used for
telecommunication signaling over analog telephone lines in the voice-frequency band.
Parameter
Configuring Basic Features
Permitted Values Default
0 or 1 1
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