Yealink SIP-T4U Series User Manual

Configuration Parameters
529
Values 1-Enabled
Default
0
Parameter
sip.unreg_with_socket_close <y0000000000xx>.cfg
Description
It enables or disables the phone to close the socket immediately when the user deregisters the cor-
responding account(s).
Permitted
Values
0-Disabled
1-Enabled
Default
0
Parameter
account.X.check_cseq.enable
[1]
<MAC>.cfg
Description
It enables or disables the phone to check if the CSeq sequence number in the request is lower than
that in the previous request on the same dialog.
Permitted
Values
0-Disabled
1-Enabled. If the CSeq sequence number in the request is lower than that in the previous request, the
phone will reject the request.
Default
1
Parameter
account.X.check_to_tag.enable
[1]
<MAC>.cfg
Description
It enables or disables the phone to check if the To-tag is carried in the To header in renewal request.
Permitted
Values
0-Disabled
1-Enabled. If the To-tag does not exist, the phone will reject the request.
Default
0
Parameter
features.call_invite_format <y0000000000xx>.cfg
Description
It configures the format of callee field in the INVITE message.
Permitted
Values
0-sip:XXX
1-tel:Number, you need to set “account.X.outbound_proxy_enable" to 1.
Default
0
Parameter
sip.escape_characters.enable <y0000000000xx>.cfg
Description
It enables or disables the phone to convert ASCII code into corresponding symbol.
Permitted
Values
0-Disabled
1-Enabled
Default
1
Case Scen-
ario
Target characters: %5F (escape character % plus the ASCII characters 5F)
1. If you want to convert the ASCII code, set the following:
sip.escape_characters.enable = 1
sip.reserve_characters = %NULL%
Result: The target characters %5F are converted to _.
2. If you do not want to convert the ASCII code, set the following:
sip.escape_characters.enable = 0
sip.reserve_characters = %

Yealink SIP-T4U Series Specifications

General

Brand	Yealink
Model	SIP-T4U Series
Category	IP Phone
Language	English