Yealink SIP-T2 SERIES Administrator's Manual page 601

Configuring Advanced Features
Parameters Permitted Values Default
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:
Account->Advanced->Shared Line
Phone User Interface:
None
String within 99
account.X.bla_number Blank
characters
Description:
Configures the BLA number for account X.
X ranges from 1 to 16 (for 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)
Example:
account.1.bla_number = 14084588327
Note: It works only if the value of the parameter ―account.X.shared_line‖ is set to 3
(Draft BLA). It is not applicable to SIP VP-T49G IP phones.
Web User Interface:
Account->Advanced->BLA Number
Phone User Interface:
None
account.X.bla_subscribe_period Integer from 60 to 7200 300
Description:
Configures the period (in seconds) of the BLA subscription for account X.
X ranges from 1 to 16 (for 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)
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