Persistent communication with changing environment

• US 6,647,001 B1
• Filed: 12/06/1999
• Issued: 11/11/2003
• Est. Priority Date: 12/06/1999
• Status: Expired due to Fees

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Bhagavath, Vijay K., OʼNeil, Joseph Thomas
• Primary Examiner(s): Ngo, Ricky
• Assistant Examiner(s): Ha, Yvonne Q.
• Application Number:
  US09/455,119
• Time in Patent Office: 1,436 Days
• Field of Search: 370/351, 370/389, 370/392, 370/394, 370/400, 370/401, 370/331, 370/338, 370/475, 455/436, 455/438, 455/439
• US Class Current: 370/331
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 47/34 ensuring sequence integrity, e.g. using sequence numbers
• CPC Class Codes: H04L 61/5084 Providing for device mobility network addressing or numbering for mobility support in wireless networks H04W8/26; mobile IP H04W80/04
• CPC Class Codes: H04M 15/56 for VoIP communications
• CPC Class Codes: H04M 15/57 for integrated multimedia messaging subsystem [IMS]
• CPC Class Codes: H04M 15/8228 Session based
• CPC Class Codes: H04M 2215/202 VoIP; Packet switched telephony
• CPC Class Codes: H04M 2215/208 IMS, i.e. Integrated Multimedia messaging Subsystem
• CPC Class Codes: H04M 2215/22 Bandwidth or usage-sensitve billing
• CPC Class Codes: H04M 2215/32 Involving wireless systems
• CPC Class Codes: H04M 2215/7833 Session based
• CPC Class Codes: H04W 36/00692 using simultaneous multiple data streams, e.g. cooperative multipoint [CoMP], carrier aggregation [CA] or multiple input multiple output [MIMO] allocation of physical resources in CoMP or in CA H04L5/0035
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

The invention provides persistent communication for address routed communication in an environment where the communication session address changes. The invention is appropriate for any address routed communication, and in particular to packet based (e.g., UDP/IP and TCP/IP) communications to mobile cellular units as the units transition or move between supporting cells. The invention provides a technique to store address information and transitory information related to the session to allow continuation of the session at the new address, thereby reducing or eliminating the need to set up the session at the new address. One application is for streaming multi-media sessions. Another application is for internet protocol (IP) telephony. The invention provides embodiments where the techniques are performed within the mobile unit, or performed in combination with a proxy server that is part of the supporting cellular system.

Claims

1. A method comprising:

conducting an address routed communication session at a communication terminal, the terminal having a first address that is used to route session information from a session source to the terminal;

capturing, at the terminal, transitory state information of the communication session when the communication session is using the first address;

determining that the terminal requires a change of the first address to a second address during the communication session;

changing the terminal address from the first address to the second address without terminating the communication session;

continuing the communication session using the second address to route session information from the session source to the terminal; and

using, at the terminal, the transitory state information of the communication session to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

2. A method according to claim 1, wherein the transitory state information includes information selected from the group consisting of frame number, sequence number, and packet number.

3. A method according to claim 1, wherein the communication session is a streaming multimedia session.

4. A method according to claim 1, wherein the communication session is a UDP/IP session.

5. A method according to claim 1, wherein the first address and second address include an internet protocol address.

6. A method according to claim 1, wherein the communication session includes a plurality of streaming multimedia sessions, the method further comprising capturing transitory state information of the plurality of streaming multimedia sessions.

7. A method according to claim 1, wherein the communication session includes an internet protocol telephony session.

8. A method according to claim 1, wherein the terminal is a cellular communication device and the communication session is a packet based session.

9. A method according to claim 1, wherein the terminal is a mobile terminal and the change of the first address to the second address is a result of movement of the terminal.

10. A method according to claim 1, wherein the communication session continues while changing the terminal address.

11. A method according to claim 1, wherein the communication session is paused but not terminated while changing the terminal address.

40. A method according to claim 1, wherein the step of using, at the terminal, the transitory state information of the communication session to continue the communication session using the second address, includes providing the captured transitory state information to the session source.

12. Computer executable software code stored on a computer readable medium, the code for address routed communication, the code comprising:

code to conduct an address routed communication session at a communication terminal, the terminal having a first address that is used to route session information from a session source to the terminal;

code to capture, at the terminal, transitory state information of the communication session when the communication session is using the first address;

code to determine that the terminal requires a change of the first address to a second address during the communication session;

code to change the terminal address from the first address to the second address without terminating the communication session;

code to continue the communication session using the second address to route session information from the session source to the terminal; and

code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

41. A computer executable software code according to claim 12, wherein the code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address, includes code to provide the captured transitory state information to the session source.

13. A computer-readable medium having computer executable software code stored thereon, the code for address routed communication, the code comprising:

code to conduct an address routed communication session at a communication terminal, the terminal having a first address that is used to route session information from a session source to the terminal;

code to capture, at the terminal, transitory state information of the communication session when the communication session is using the first address;

code to determine that the terminal requires a change of the first address to a second address during the communication session;

code to change the terminal address from the first address to the second address without terminating the communication session;

code to continue the communication session using the second address to route session information from the session source to the terminal; and

code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address,

wherein the terminal is a cellar communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

42. A computer-readable medium according to claim 13, wherein the code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address, includes code to provide the captured transitory state information to the session source.

14. A programmed computer for address routed communication, comprising:

a memory having at least one region for storing computer executable program code; and

a processor for executing the program code stored in the memory;

wherein the program code includes;

code to conduct an address routed communication session at a communication terminal, the terminal having a first address that is used to route session information from a session source to the terminal;

code to capture, at the terminal, transitory state information of the communication session when the communication session is using the first address;

code to determine that the terminal requires a change of the first address to a second address during the communication session;

code to change the terminal address from the first address to the second address without terminating the communication session;

code to continue the communication session using the second address to route session information from the session source to the terminal; and

code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

43. A programmed computer according to claims 14, wherein the code to use, at the terminal, the transitory state information of the communication session to continue the communication session using the second address, includes code to provide the captured transitory state information to the session source.

15. A method comprising:

conducting an internet protocol address routed streaming multi-media communication session at a mobile cellular communication terminal, the terminal having a first internet protocol address that is used to route session information from a streaming source to the terminal;

capturing, at the terminal, transitory state information of the communication session when the communication session is using the first address;

determining that the terminal requires a change of the first address to a second internet protocol address during the communication session ms a result of cellular information available to the terminal;

changing the terminal address from the first address to the second address with instructions from the terminal without terminating the communication session;

continuing the communication session using the second address to route session information from the session source to the terminal with instructions from the terminal; and

using, at the terminal, the transitory state information of the communication session to continue the communication session using the second address,

wherein the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

44. A method according to claim 15, wherein the step of using, at the terminal, the transitory state information of the communication session to continue the communication session using the second address, includes providing the captured transitory state information to the streaming source.

16. A method comprising:

conducting an address routed communication session with a communication terminal using a first address that is used to route session information from a source to the terminal;

receiving, from the terminal, transitory state information of the communication session captured by the terminal when the communication session is using the first address;

determining that the first address of the terminal will change to a second address during the communication session;

changing the first address to the second address without terminating the communication session;

continuing the communication session using the second address to route the session information from the source to the terminal; and

using the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

17. A method according to claim 16, further comprising using a proxy server to conduct the communication session with the terminal.

18. A method according to claim 16, wherein the transitory state information includes information selected from the group consisting of frame number, sequence number, and packet number.

19. A method according to claim 16, wherein the communication session is a streaming multimedia session.

20. A method according to claim 16, wherein the communication session includes a plurality of streaming multimedia sessions, the method further comprising using transitory state information of the plurality of streaming multimedia sessions to continue the sessions.

21. A method according to claim 16, wherein the communication session includes an internet protocol telephony session.

22. A method according to claim 16, wherein the terminal is a cellular communication device and the communication session is a packet based session.

23. A method according to claim 16, wherein the terminal is a mobile terminal and the change of the first address to the second address is a result of movement of the terminal.

24. A method according to claim 16, wherein the communication session continues while changing the first address to the second address.

25. A method according to claim 16, wherein the communication session is paused but not terminated while changing the first address to the second address.

26. Computer executable software code stored on a computer readable medium, the code for address routed communication, the code comprising:

code to conduct an address routed communication session with a communication terminal using a first address that is used to route session information from a source to the terminal;

code to receive, from terminal, transitory state information of the communication session captured by the terminal when the communication session is using the first address;

code to determine that the first address of the terminal will change to a second address during the communication session;

code to change the first address to the second address without terminating the communication session;

code to continue the communication session using the second address to route the session information from the source to the terminal; and

code to use the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

27. A computer-readable medium having computer executable software code stored thereon, the code for address routed communication, the code comprising:

code to conduct an address routed communication session with a communication terminal using a first address that is used to route session information from a source to the terminal;

code to receive, from the terminal, transitory state information of the communication session captured by the terminal when the communication session is using the first address;

code to determine that the first address of the terminal will change to a second address during the communication session;

code to change the first address to the second address without testing the communication session;

code to continue the communication session using the second address to route the session information from the source to the terminal; and

code to use the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a fist cell and the second address corresponds to an address assigned for a second cell.

28. A programmed computer for address routed communication, comprising:

a memory having at least one region for storing computer executable program code; and

a processor for executing the program code stored in the memory;

wherein the program code includes;

code to conduct an address routed communication session with a communication terminal using a first address that is used to route session information from a source to the terminal;

code to receive, from the terminal, transitory state information of the communication session captured by the terminal when the communication session is using the first address;

code to determine that the first address of the terminal will change to a second address during the communication session;

code to change the first address to the second address without terminating the communication session;

code to continue the communication session using the second address to route the session information from the source to the terminal; and

code to use the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

29. An apparatus comprising:

a communication terminal for conducting an address routed communication session, the terminal further comprising;

a circuit for receiving session information with a first address, the first address used to route the session information from a source to the terminal;

a circuit, at the terminal, for capturing transitory state information of the communication session when the communication session is using the first address;

a circuit for determining that the terminal requires a change of the first address to a second address during the communication session;

a circuit for changing the terminal address from the first address to the second address without terminating the communication session;

a circuit for continuing the communication session with the second address, the second address used to route the session information from the source to the terminal; and

a circuit, at the terminal, for using the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

30. An apparatus according to claim 29, wherein the terminal is a cellular communication device and the communication session is a packet based session.

31. An apparatus according to claim 29, wherein the terminal is a mobile terminal and the change of the first address to the second address is a result of movement of the terminal.

32. An apparatus according to claim 29, wherein the address routed communication session is a streaming multi-media session and the terminal receives the streaming multi-media session.

33. An apparatus according to claim 29, wherein the address routed communication session is an internet protocol telephony communication session and the terminal is internet telephony capable.

45. An apparatus according to claim 29, wherein the circuit, at the terminal, for using the transitory state information of the communication session to continue the communication session using the second address, includes a circuit for providing the captured transitory state information to the source.

34. A system comprising:

a server for conducting an address routed communication session with a communication terminal;

a circuit for sending session information with a first address, the first address used to route the session information from the server to the terminal;

a circuit for receiving, from the terminal, transitory state information of the communication session captured by the terminal when the communication session is using the first address;

a circuit for determining that the terminal requires a change of the first address to a second address during the communication session;

a circuit for changing the address used to route the session information from the first address to the second address without terminating the communication session;

a circuit for continuing the communication session with the second address, the second address used to route session information from the server to the terminal; and

a circuit for using the transitory state information of the communication session received from the terminal to continue the communication session using the second address,

wherein the terminal is a cellular communication device and the first address corresponds to an address assigned for a first cell and the second address corresponds to an address assigned for a second cell.

35. A system according to claim 34, further comprising a proxy server, used in the communication session with the terminal.

36. A system according to claim 34, wherein the address routed communication session is a streaming multi-media session and the server is the source of the streaming multi-media session.

37. A system according to claim 34, wherein the address routed communication session is an internet protocol telephony communication session and the terminal is internet telephony capable.

38. A system according to claim 34, wherein the terminal is a cellular communication device and the communication session is a packet based session.

39. A system according to claim 34, wherein the terminal is a mobile terminal and the change of the first address to the second address is a result of movement of the terminal.