Grandstream Networks DP750 Administration Manual page 49

is increased to (2*T1) and then (4*T1). Request re-transmit retries would continue
until a maximum amount of time defined by T2. Default is 0.5 seconds.
SIP T2 Timeout Identifies maximum retransmission interval for non-INVITE requests and INVITE
responses. Retransmitting and doubling of T1 continues until it reaches T2 value.
Default is 4 seconds.
SIP Timer D Configures SIP timer D defined in RFC3261. Range of values 0-64. Default is 0.
Enable OPTIONS Enables OPTIONS Keep Alive, to check SIP server. Default is No.
Keep Alive
OPTIONS Keep Time interval for OPTIONS Keep Alive feature in seconds. Range of values is
Alive Interval 1–64800. Default is 30.
Maximum number of lost packets for OPTIONS Keep Alive feature before the phone
OPTIONS Keep
Alive Max Lost sends a re-registration. Range of values 3-10. Default is 3.
Removes outbound proxy information from "Route" header when sending SIP
Remove OBP from
Route Header packets. Default is No.
Adds "SIP Instance ID" attribute to "Contact" header in REGISTER request as
Support SIP
Instance ID defined in IETF SIP outbound draft. Default is No.
Hold Target Before Sends re-INVITE to hold transfer target before sending REFER message to
Refer transferee. Default is Yes.
Refer-To Use Target Includes target's "Contact" header information in "Refer-To" header when using
Contact attended transfer. Default is No.
SUBSCRIBE for Sends periodic "SUBSCRIBE" requests (depends on "Register Expiration"
MWI parameter) for message waiting indication service. Default is No.
Enable 100rel Appends "100rel" attribute to the "required" header of the initial signaling messages.
Default is No.
TEL URI Indicates E.164 number in "From" header by adding "User=Phone" parameter or
using "Tel:" in SIP packets, if the base has an assigned PSTN Number.
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Please consult your carrier before changing this parameter. Default is Disabled.
Disabled: Will use "SIP User ID" information in the Request-Line and "From"
header.
User=Phone: "User=Phone" parameter will be attached to the Request-Line
and "From" header in the SIP request to indicate the E.164 number. If set to
"Enable".
Enabled: "Tel:" will be used instead of "sip:" in the SIP request.
DP750/DP720 Administration Guide
Version 1.0.11.4
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