Session initiation protocol retransmission method
View Patent ↗For a network server ( 35 ) communicating with a wireless unit ( 10 ) via a Session Initiation Protocol, a retransmission method ( 50 ) first sets a timer based upon a time likely for a mobile unit to respond ( 54 ). Then the network server waits for a response ( 56 ). When the timer set for the kind of mobile unit being used expires ( 64 ), a retransmit of the original SIP request takes place ( 68 ). Optionally, modes for waiting may include a linear mode ( 72 ) and an exponential mode ( 74 ).
1. A message retransmission method for a server and a mobile unit in a Session Initiation Protocol (SIP) based communication system, the message retransmission method comprising the step of:
sending a SIP message by the server to the mobile unit;
setting by the server a timer based upon a mobile unit type, network type and a time likely for response by the mobile unit type; and
waiting by the server until the timer expires before sending a retransmission of the SIP message.
2. The message retransmission method as claimed in claim 1 , wherein the communication system is a Code Division Multiple Access (CDMA) type of communication system.
3. The message retransmission method as claimed in claim 1 , wherein the communication system is a Global System Mobile (GSM).
4. The message retransmission method as claimed in claim 1 , wherein the communication system is an iDEN communication system.
5. The message retransmission method as claimed in claim 1 , wherein the step of setting by the server a timer includes a step of starting the timer.
6. The message retransmission method as claimed in claim 1 , wherein the step of setting by the server the timer includes a step of setting a retransmission counter to zero.
7. The message retransmission method as claimed in claim 6 , wherein there is further included steps of:
determining by the server a response from the mobile unit; and
determining by the server a lack of a response by the mobile unit based on expiration of the timer.
8. The message retransmission method as claimed in claim 7 , wherein if a SIP 1XX response was determined by the server, there is further included the steps of:
stopping the timer; and
repeating the step of waiting by the server.
9. The message retransmission method as claimed in claim 7 , wherein if the response determined by the server is a SIP 2XX–6XX message, there is further included the steps of:
stopping the timer; and
ending the message retransmission method.
10. The message retransmission method as claimed in claim 7 , wherein if the timer expires, there is further included a step of incrementing the retransmission counter by one.
11. The message retransmission method as claimed in claim 10 , wherein:
if the retransmission counter is greater than a maximum retransmission attempts, there is further included a step of ending the message retransmission method; and
if the retransmission counter is less than or equal to the maximum retransmission attempts, there is further included a step of retransmitting the SIP message by the server.
12. The message retransmission method as claimed in claim 11 , wherein there is further included a step of determining a retransmission mode.
13. The message retransmission method as claimed in claim 12 , wherein if the retransmission mode is a first mode, there is further included a step of maintaining a constant value of the timer.
14. The message retransmission method as claimed in claim 12 , wherein if the retransmission mode is a second mode, there is further included a step of increasing a value of the timer exponentially.
15. A message retransmission method between a client and a server using Session Initiation Protocol (SIP), the message retransmission method comprising the steps of:
sending a SIP message between the server and the client;
setting a timer based upon a client type, network characteristics and a first time likely for a response by the client type; and
waiting until the timer expires before sending a retransmission of the SIP message.
16. The message retransmission method as claimed in claim 15 , wherein there is further included steps of:
utilizing Code Division Multiple Access (CDMA) between the server and the client; and
setting an initial value of the timer equal to approximately four seconds.
17. The message retransmission method as claimed in claim 15 , wherein there is further included steps of:
utilizing a Global System Mobile (GSM) protocol between the client and the server; and
setting an initial value of the timer equal to approximately four seconds.
18. The message retransmission method as claimed in claim 15 , wherein there is further included steps of:
utilizing an iDEN interface between the client and the server; and
setting an initial value of the timer equal to approximately one second.
19. The message retransmission method as claimed in claim 15 , wherein there is further included a step of waiting until expiration of the timer before sending a retransmission of the SIP message between the server and the client.
20. The message retransmission method as claimed in claim 15 , wherein there is further included a step of limiting a number of retransmissions of the SIP message between the client and the server to a predetermined number.
21. The message retransmission method as claimed in claim 15 , wherein there is further included a step of maintaining a constant value of the timer for subsequent retransmissions of the SIP message.
22. The message retransmission method as claimed in claim 15 , wherein there is further included a step of exponentially increasing a value of the timer for subsequent retransmissions of the SIP message.
23. The message retransmission method as claimed in claim 15 , wherein there is further included a step of adjusting a value of the timer for an initial setting.
24. The message retransmission method as claimed in claim 15 , wherein there is further included a step of adjusting a value of the timer for a a subsequent retransmission.