Jitter buffer management for mobile communication handoffs

• US 7,440,430 B1
• Filed: 03/30/2004
• Issued: 10/21/2008
• Est. Priority Date: 03/30/2004
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Jagadeesan, Ramanathan T., Chung, Andrew C.
• Primary Examiner(s): Levitan; Dmitry
• Application Number:
  US10/812,604
• Time in Patent Office: 1,666 Days
• Field of Search: 370/310, 370/312, 370/314, 370/328, 370/332, 370/333, 370/337, 370/347, 370/331, 455/403, 455/405, 455/422, 455436-442
• US Class Current: 370/331
• CPC Class Codes: H04L 65/764 at the destination reformatting of additional data in video clients H04N21/4355
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04W 28/10 Flow control between communication endpoints
• CPC Class Codes: H04W 36/023 Buffering or recovering information during reselection
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection

Abstract

A method of providing communication service includes determining a first playback delay based on one or more network characteristics of a first network and one or more network characteristics of a second network. The method also includes storing media received from the first network in a first buffer and playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on the first playback delay. The method further includes detecting a handoff trigger and storing media received from the second network in a second buffer, in response to detecting the handoff trigger. The method also includes playing media received from the second network.

Claims

1. A method of providing communication service comprising:

determining a first playback delay based on a maximum jitter of a first network, a maximum jitter of a second network, a maximum delay of the second network, and a minimum delay of the first network;

storing media received from the first network in a first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on the first playback delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger; and

playing media received from the second network.

2. The method of claim 1, wherein playing media received from the second network comprises:

determining a second playback delay based on the maximum jitter of the second network, the maximum jitter of the first network, a minimum delay of the second network and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second playback delay.

3. The method of claim 1, wherein determining the first playback delay comprises determining the first playback delay based on a greater of a maximum jitter of the first network and a sum of a maximum jitter of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

4. The method of claim 3, wherein playing media received from the second network comprises:

determining a second playback delay based on a greater of the maximum jitter of the second network and a difference between the maximum jitter of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second playback delay.

5. The method of claim 1, wherein determining the first playback delay comprises determining the first playback delay based on a greater of a maximum jitter of the first network and a difference between a maximum jitter of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

6. A method of providing communication service comprising:

determining a first minimum delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

determining a first current delay for a first buffer, wherein the first current delay is greater than or equal to a first minimum delay;

storing media received from the first network in the first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detecting a handoff trigger; and

storing media received from the second network in a second buffer, in response to the handoff trigger, in response to detecting the handoff trigger; and

playing media received from the second network.

7. The method of claim 6, wherein playing media received from the first network comprises:

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

adjusting the first current delay based on one or more network characteristics of the first network, wherein the adjusted first current delay is greater than or equal to the first minimum delay; and

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the adjusted first current delay.

8. The method of claim 6, wherein determining the first playback delay comprises determining the first minimum delay based on a low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

9. The method of claim 8, wherein playing media received from the second network comprises:

determining a second minimum delay based on a low jitter value of the second network, a nominal jitter value of the first network, a minimum delay of the second network, and a maximum delay of the first network;

determining a second current delay for a second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

10. The method of claim 6, wherein determining the first playback delay comprises determining the first minimum delay based on a greater of a low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

11. The method of claim 8, wherein playing media received from the second network comprises:

determining a second minimum delay based on a greater of a low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

determining a second current delay for a second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

12. The method of claim 6, wherein determining the first playback delay comprises determining the first minimum delay based on a greater of a low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

13. A method of providing communication service comprising:

determining a first target delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

determining a first current delay for a first buffer, wherein the first current delay is greater than or equal to a low jitter value of the first network;

storing media received from the first network in the first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger;

increasing the first current delay, if the first current delay is less than the first target delay;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the increased first current delay;

detecting a handoff termination; and

playing media received from the second network, in response to detecting the handoff termination.

14. The method of claim 13, wherein determining the first playback delay comprises determining the first target delay based on a low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

15. The method of claim 13, wherein determining the first playback delay comprises determining the first target delay based on a greater of a low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

16. The method of claim 13, further comprising determining the first target delay based on a greater of the low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

17. The method of claim 13, wherein playing media from the second network comprises:

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to a low jitter value of the second network;

playing media received from the second network, in response to detecting the handoff termination, after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay;

detecting a second handoff trigger;

increasing the second current delay, if the second current delay is less than a second target delay, the second target delay based on a greater of the low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on at least the increased second current delay;

detecting a second handoff termination; and

playing media received from the first network, in response to detecting the second handoff termination.

18. A device for providing communication service comprising:

a first interface operable to receive media from a first network;

a second interface operable to receive media from a second network;

a first buffer operable to store media received from the first network;

a second buffer operable to store media received from the second network;

an output module operable to play media; and

a processor operable to;

determine a first playback delay based on a maximum jitter of the first network, a maximum jitter of the second network, a maximum delay of the second network, and a minimum delay of the first network;

store media received from the first network in the first buffer;

play media received from the first network, using the output module, after the media received from the first network has been stored in the first buffer an amount of time based on at least the first playback delay;

detect a handoff trigger;

store media received from the second network in the second buffer, in response to detecting the handoff trigger; and

play media received from the second network.

19. The device of claim 18, wherein the processor is further operable to play media received from the second network by:

determining a second playback delay based on the maximum jitter of the second network, the maximum jitter of the first network, a minimum delay of the second network, and a maximum delay of the first network;

play media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

20. The device of claim 18, wherein the processor is further operable to determine the first playback delay based on a greater of a maximum jitter of the first network and a sum of a maximum jitter of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

21. The device of claim 20, wherein the processor is further operable to play media received from the second network by:

determining a second playback delay based on a greater of the maximum jitter of the second network and a difference between the maximum jitter of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

play media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

22. The device of claim 18, wherein the processor is further operable to determine the first playback delay based on a greater of a maximum jitter of the first network and a difference between a maximum jitter of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

23. A device for providing communication service comprising:

a first interface, operable to receive media from a first network;

a second interface, operable to receive media from a second network;

a first buffer, operable to store media received from the first network;

a second buffer, operable to store media received from the second network;

an output module, operable to play media; and

a processor operable to;

determine a first minimum delay based on one or more network characteristics of the first network and one or more network characteristics of the second network;

determine a first current delay for the first buffer, wherein the first current delay is greater than or equal to the first minimum delay;

store media received from the first network in the first buffer;

play media received from the first network, using the output module, after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detect a handoff trigger;

store media received from the second network in the second buffer, in response to the handoff trigger; and

play media received from the second network.

24. The device of claim 23, wherein the processor is further operable to play media received from the first network by:

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

adjusting the first current delay based on one or more network characteristics of the first network, wherein the adjusted first current delay is greater than or equal to the first minimum delay; and

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the adjusted first current delay.

25. The device of claim 23, wherein the processor is further operable to determine the first minimum delay by determining the first minimum delay based on a low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

26. The device of claim 25, wherein the processor is further operable to play media received from the second network by:

determining a second minimum delay based on a low jitter value of the second network, a nominal jitter value of the first network, a minimum delay of the second network, and a maximum delay of the first network;

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

play media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

27. The device of claim 23, wherein the processor is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of a low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

28. The device of claim 27, wherein the processor is further operable to play media received from the second network by:

determining a second minimum delay based on a greater of a low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

play media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

29. The device of claim 23, wherein the processor is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of a low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

30. A device for providing communication service comprising:

a first interface, operable to receive media from a first network;

a second interface, operable to receive media from a second network;

a first buffer, operable to store media received from the first network;

a second buffer, operable to store media received from the second network;

an output module, operable to play media; and

a processor, operable to;

determine a first target delay based on one or more network characteristics of the first network and one or more network characteristics of the second network;

determine a first current delay for the first buffer, wherein the first current delay is greater than or equal to a low jitter value of the first network;

store media received from the first network in the first buffer;

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detect a handoff trigger;

store media received from the second network in the second buffer, in response to the handoff trigger;

increase the first current delay, if the first current delay is less than a first target delay,

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the increased first current delay;

detect a handoff termination; and

play media received from the second network, in response to detecting the handoff termination, after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

31. The device of claim 30, wherein the processor is further operable to determine the first target delay based on the low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

32. The device of claim 30, wherein the processor is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

33. The device of claim 30, wherein the processor is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

34. The device of claim 30, wherein the processor is further operable to:

determine a second current delay for the second buffer, wherein the second current delay is greater than or equal to a low jitter value of the second network;

play media received from the second network, in response to detecting the handoff termination, after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay;

detect a second handoff trigger;

increase the second current delay, if the second current delay is less than a second target delay, the second target delay based on a greater of the low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

play media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on at least the increased second current delay;

detect a second handoff termination; and

play media received from the first network, in response to detecting the second handoff termination.

35. Logic for providing telecommunication service, the logic encoded in media and operable when executed to perform the steps of:

determining a first playback delay based on a maximum jitter of a first network, a maximum jitter of a second network, a maximum delay of the second network, and a minimum delay of the first network;

storing media received from the first network in a first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first playback delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger; and

playing media received from the second network.

36. The logic of claim 35, wherein the logic is further operable to play media received from the second network by:

determining a second playback delay based on the maximum jitter of the second network, the maximum jitter of the first network, a minimum delay of the second network, and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

37. The logic of claim 35, wherein the logic is further operable to determine the first playback delay based on a greater of a maximum jitter of the first network and a sum of a maximum jitter of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

38. The logic of claim 37, wherein the logic is further operable to play media received from the second network by:

determining a second playback delay based on a greater of the maximum jitter of the second network and a difference between the maximum jitter of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

39. The logic of claim 35, wherein the logic is further operable to determine the first playback delay based on a greater of a maximum jitter of the first network and a difference between the maximum jitter of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

40. Logic for providing telecommunication service, the logic encoded in media and operable when executed to perform the steps of:

determining a first minimum delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

determining a first current delay for a first buffer, the first current delay greater than or equal to the first minimum delay;

storing media received from the first network in the first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger; and

playing media received from the second network.

41. The logic of claim 40, wherein the logic is further operable to play media received from the first network by:

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

adjusting the first current delay based on one or more network characteristics of the first network, wherein the adjusted first current delay is greater than or equal to the first minimum delay; and

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the adjusted first current delay.

42. The logic of claim 40, wherein the logic is further operable to determine the first minimum delay by determining the first minimum delay based on a low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

43. The logic of claim 42, wherein the logic is further operable to play media received from the second network by:

determining a second minimum delay based on a low jitter value of the second network, a nominal jitter value of the first network, a minimum delay of the second network, and a maximum delay of the first network;

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

44. The logic of claim 40, wherein the logic is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of the low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

45. The logic of claim 44, wherein the logic is further operable to play media received from the second network by:

determining a second minimum delay based on a greater of a low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

46. The logic of claim 40, wherein the logic is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of a low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

47. Logic for providing telecommunication service, the logic encoded in media and operable when executed to perform the steps of:

determining a first target delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

determining a first current delay for a first buffer, wherein the first current delay is greater than or equal to a low jitter value of the first network;

storing media received from the first network in the first buffer;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger;

increasing the first current delay, if the first current delay is less than the first target delay;

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the increased first current delay;

detecting a handoff termination; and

playing media received from the second network, in response to detecting the handoff termination.

48. The logic of claim 47, wherein the logic is further operable to determine the first target delay based on the low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

49. The logic of claim 47, wherein the logic is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

50. The logic of claim 47, wherein the logic is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

51. The logic of claim 47, wherein the logic is further operable to play media received from the second network by:

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to a low jitter value of the second network;

playing media received from the second network, in response to detecting the handoff termination, after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay;

detecting a second handoff trigger;

increasing the second current delay, if the second current delay is less than a second target delay, the second target delay based on a greater of the low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on at least the increased second current delay;

detecting a second handoff termination; and

playing media received from the first network, in response to detecting the second handoff termination.

52. A system for providing communication service comprising:

a first network, operable to transmit media to a mobile station;

a second network, operable to transmit media to a mobile station; and

a communication device, operable to;

determine a first playback delay based on a maximum jitter of the first network, a maximum jitter of the second network, a maximum delay of the second network, and a minimum delay of the first network;

store media received from the first network in a first buffer;

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first playback delay;

detecting a handoff trigger;

storing media received from the second network in a second buffer, in response to detecting the handoff trigger; and

playing media received from the second network.

53. The system of claim 52, wherein the communication device is further operable to play media received from the second network by:

determining a second playback delay based on the maximum jitter of the second network, the maximum jitter of the first network, a minimum delay of the second network, and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

54. The system of claim 52, wherein the communication device is further operable to determine the first playback delay based on a greater of the maximum jitter of the first network and a sum of the maximum jitter of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

55. The system of claim 54, wherein the communication device is further operable to play media received from the second network by:

determining a second playback delay based on a greater of the maximum jitter of the second network and a difference between the maximum jitter of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on a second playback delay.

56. The system of claim 52, wherein the communication device is further operable to determine the first playback delay based on a greater of a maximum jitter of the first network and a difference between the maximum jitter of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

57. A system for providing communication service comprising:

a first network, operable to transmit media to a mobile station;

a second network, operable to transmit media to a mobile station; and

a communication device, operable to;

determine a first minimum delay based on one or more network characteristics of the first network and one or more network characteristics of the second network;

determine a first current delay for a first buffer, the first current delay greater than or equal to the first minimum delay;

store media received from the first network in the first buffer;

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detect a handoff trigger;

store media received from the second network in the second buffer, in response to detecting the handoff trigger; and

play media received from the second network.

58. The system of claim 57, wherein the communication device is further operable to play media received from the first network by:

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

adjusting the first current delay based on one or more network characteristics of the first network, wherein the adjusted first current delay is greater than or equal to the first minimum delay; and

playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the adjusted first current delay.

59. The system of claim 57, wherein the communication device is further operable to determine the first minimum delay by determining the first minimum delay based on a low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

60. The system of claim 59, wherein the communication device is further operable to play media received from the second network by:

determining a second minimum delay based on a low jitter value of the second network, a nominal jitter value of the first network, a minimum delay of the second network, and a maximum delay of the first network;

determining a second current delay for a second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

61. The system of claim 57, wherein the communication device is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of the low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

62. The system of claim 61, wherein the communication device is further operable to play media received from the second network by:

determining a second minimum delay based on a greater of a low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

determining a second current delay for a second buffer, wherein the second current delay is greater than or equal to the second minimum delay; and

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay.

63. The system of claim 57, wherein the communication device is further operable to determine the first minimum delay by determining the first minimum delay based on a greater of a low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

64. A system for providing communication service comprising:

a first network, operable to transmit media to a mobile station;

a second network, operable to transmit media to a mobile station; and

a communication device, operable to;

determine a first target delay based on one or more network characteristics of the first network and one or more network characteristics of the second network;

determine a first current delay for a first buffer, wherein the first current delay is greater than or equal to a low jitter value of the first network;

store media received from the first network in the first buffer;

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

detect a handoff trigger;

store media received from the second network in the second buffer, in response to detecting the handoff trigger;

increase the first current delay, if the first current delay is less than a first target delay;

play media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the increased first current delay;

detect a handoff termination; and

play media received from the second network, in response to detecting the handoff termination.

65. The system of claim 64, wherein the communication device is further operable to determine the first target delay based on the low jitter value of the first network, a nominal jitter value of the second network, a maximum delay of the second network, and a minimum delay of the first network.

66. The system of claim 64, wherein the communication device is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a sum of a nominal jitter value of the second network and a maximum delay difference, wherein the maximum delay difference is equal to a difference between a maximum delay of the second network and a minimum delay of the first network.

67. The system of claim 64, wherein the communication device is further operable to determine the first target delay based on a greater of the low jitter value of the first network and a difference between a nominal jitter value of the second network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the first network and a maximum delay of the second network.

68. The system of claim 64, wherein the communication device is further operable to play media received from the second network by:

determining a second current delay for the second buffer, wherein the second current delay is greater than or equal to a low jitter value of the second network;

playing media received from the second network, in response to detecting the handoff termination, after the media received from the second network has been stored in the second buffer an amount of time based on the second current delay;

detecting a second handoff trigger;

increasing the second current delay, if the second current delay is less than a second target delay, the second target delay based on a greater of the low jitter value of the second network and a difference between a nominal jitter value of the first network and a minimum delay difference, wherein the minimum delay difference is equal to a difference between a minimum delay of the second network and a maximum delay of the first network;

playing media received from the second network after the media received from the second network has been stored in the second buffer an amount of time based on at least the increased second current delay;

detecting a second handoff termination; and

playing media received from the first network, in response to detecting the second handoff termination.

69. A system for providing communication service comprising:

means for determining a first playback delay based on a maximum jitter of a first network, a maximum jitter of a second network, a maximum delay of the second network, and a minimum delay of the first network;

means for storing media received from the first network in a first buffer;

means for playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on the first playback delay;

means for detecting a handoff trigger;

means for storing media received from the second network in a second buffer in response to detecting the handoff trigger; and

means for playing media received from the second network.

70. A system for providing communication service comprising:

means for determining a first minimum delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

means for determining a first current delay for a first buffer, wherein the first current delay is greater than or equal to a first minimum delay;

means for storing media received from the first network in the first buffer;

means for playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

means for detecting a handoff trigger;

means for storing media received from the second network in a second buffer, in response to detecting the handoff trigger;

means for playing media received from the second network.

71. A method of providing communication service comprising:

means for determining a first target delay based on one or more network characteristics of a first network and one or more network characteristics of a second network;

means for determining a first current delay for a first buffer, wherein the first current delay is greater than or equal to a low jitter value of the first network;

means for storing media received from the first network in the first buffer;

means for playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the first current delay;

means for storing media received from the second network in a second buffer;

means for detecting a handoff trigger;

means for increasing the first current delay, if the first current delay is less than the first target delay;

means for playing media received from the first network after the media received from the first network has been stored in the first buffer an amount of time based on at least the increased first current delay;

means for detecting a handoff termination; and

means for playing media received from the second network, in response to detecting the handoff termination.