Cisco IP Phone 6851

DescriptionParameter
Controls whether to hold call leg with transfer target before sending
REFER to the transferee when initiating a fully-attended call transfer
(where the transfer target has answered).
Default: No
Hold Target Before Refer
When enabled and the Notify message body is too big causing
fragmentation, the Notify message xml dialog is simplified; Session
Description Protocol (SDP) is not included in the dialog xml content.
Dialog SDP Enable
If set to yes, it configures the phone to immediately handle NOTIFY
sipfrag messages.
Keep Referee When Refer Failed
Display the Diversion info included in SIP message on LCD or not.Display Diversion Info
Show the caller ID from the SIP INVITE message “From” header when
set to Yes, even if the call is an anonymous call. When the parameter
is set to no, the phone displays "Anonymous Caller" as the caller ID.
Display Anonymous From Header
Supports the content-encoding gzip feature. The options are none and
gzip.
If gzip is selected, the SIP message header contains the string
“Accept-Encoding: gzip”, and the phone is able to process the SIP
message body, which is encoded with the gzip format.
Sip Accept Encoding
The options are No and Yes. If No is selected, no changes are made.
The default value is No.
If Yes is selected, it disables the display name in “Directory”, “Call
History”, and in the “To” header during an outgoing call.
Disable Local Name To Header
Sets if the phone uses IPv4 or IPv6.
Default: IPv4.
SIP IP Preference
Select Yes to enable or No to disable.
Default: No
Disable Local Name to Header
SIP Timer Values (sec)
DescriptionParameter
RFC 3261 T1 value (RTT estimate) that can range from 0 to 64 seconds.
Default: 0.5 seconds
SIP T1
RFC 3261 T2 value (maximum retransmit interval for non-INVITE
requests and INVITE responses) that can range from 0 to 64 seconds.
Default: 4 seconds
SIP T2
Cisco IP Phone 6800 Series Multiplatform Phones Administration Guide
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