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SIP T2 (msec): Determines the maximum retransmission interval
as defined in RFC3261. For example, when an unreliable transport
protocol is used, general requests are retransmitted at an interval
which starts at T1 and doubles until reaches T2. If a provisional
response is received, retransmission continue but at an interval of T2.
(Default Value: 4000ms) **
SIP T4 (msec): T4 represents the amount of time the network
takes to clear message between client and server transactions as
defined in RFC3261. For example, when working with an unreliable
transport protocol, T4 determines the time that UAS waits after
receiving an ACK message and before terminating the transaction.
(Default Value: 5000) **
Invite Linger Timer: After sending an ACK for an INVITE final
response, a client cannot be sure that the server has received the
ACK message. The client should be able to retransmit the ACK upon
receiving retransmissions of the final response for this timer. This
timer is also used when a 2xx response is sent for an incoming Invite.
In this case, the ACK is not part of the Invite transaction.
General Linger Timer: After a UAS sends a final response, the UAS
cannot be sure that the client has received the response message.
The UAS should be able to retransmit the response upon receiving
retransmissions of the request based on this timer.
Cancel General No Response Time (msec): When sending a
CANCEL request on a General transaction, the User Agent waits
cancel General No Response Timer milliseconds before timeout
termination if there is no response for the cancelled
transaction(Default Value: 10000ms).**
General Request Timeout Timer (msec): After sending a
General request, the User Agent waits for a final response general
Request Timeout Timer milliseconds before timeout termination (in
this time the User Agent retransmits the request every T1,
2*T1,…T2,…milliseconds)**
Cancel Invite No Response Timer (msec): When sending a
CANCEL request on an Invite request, the User Agent waits this
timer before timeout termination if there is no response for the
cancelled transaction.
Provisional Timer (msec): The provisionalTimer is set when
receiving a provisional response on an INVITE transaction. The
transaction will stop retransmissions of the INVITE request and will
wait for a final response until the provisionTimer expires. If you set
the provisionTimer to 0, no timer is set. The INVITE transaction will
wait indefinitely for the final response.
First Response Timer (msec): When sending a request out, the
User Agent waits this timer for any response received from UAS. If
timer is expired and no any SIP message is received, the User Agent