Radio network control

• US 8,160,020 B2
• Filed: 06/25/2001
• Issued: 04/17/2012
• Est. Priority Date: 06/25/2001
• Status: Expired due to Term

• Current Assignee: Ericsson Evdo, Inc. (CommScope Holding Company, Inc.)
• Original Assignee: Airvana Incorporated (CommScope Holding Company, Inc.)
• Inventors: Eyuboglu, M. Vedat, Barabell, Arthur J., Cherian, Sanjay
• Primary Examiner(s): Patel, Jayanti K
• Assistant Examiner(s): ZHU, BO HUI ALVIN
• Application Number:
  US09/891,103
• Publication Number:
  US 20020196749A1
• Time in Patent Office: 3,949 Days
• Field of Search: 370328-331, 370/337, 370/341, 370/443, 370/389, 370/395.1, 370/395, 370/3, 370/31, 370/395.32, 455/432.1, 455/434, 455/436, 455/440, 455/442, 455/445, 455/450
• US Class Current: 370/331
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04L 61/4535 using an address exchange platform which sets up a session between two nodes, e.g. rendezvous servers, session initiation protocols [SIP] registrars or H.323 gatekeepers
• CPC Class Codes: H04W 36/0011 for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/0019 adapted for mobile IP [MIP]
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

In connection with a mobile wireless subnetwork having multiple radio network controllers and multiple radio nodes, a session established for an access terminal is associated with a serving radio network controller. The association is maintained as the access terminal moves from the coverage area of one radio node to the coverage area of another radio node within the same subnetwork. Access channel packets are routed from an access terminal having an existing session to the serving radio network controller by determining the IP address of the serving radio network controller using a session identifier.

Claims

1. A method comprising:

enabling many-to-many communication among radio network controllers and radio nodes through a packet network,

establishing a first session for a first access terminal on a first radio network controller through a first radio node, wherein the first session is established when the first access terminal is dormant, and

maintaining the first session on the first radio network controller as the first access terminal moves from a coverage area of the first radio node to any portion of a coverage area of a second radio node through which a second access terminal has a second session on a second radio network controller, wherein the first session is maintained when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

2. The method of claim 1 also comprising:

establishing a first traffic channel between the first access terminal and the first radio network controller of the network through the first radio node when the first access terminal is in the coverage area of the first radio node,

establishing a second traffic channel between the second access terminal and the second radio network controller of the network through the second radio node when the second access terminal is in the coverage area of the second radio node, and

maintaining the first traffic channel between the first access terminal and the first radio network controller without requiring the first traffic channel to pass through another radio network controller when the first access terminal moves from the coverage area of the first radio node to any portion of the coverage area of the second radio node.

3. The method of claim 2 further comprising:

sending an access channel message from the first access terminal to the first radio network controller through the second radio node.

4. The method of claim 2 further comprising:

signaling between the first radio network controller and the second radio network controller.

5. The method of claim 2 further comprising:

routing access channel packets received from the first access terminal at the second radio node to the first radio network controller by determining an Internet protocol address of the first radio network controller.

6. The method of claim 5 wherein the Internet protocol address is determined using a session identifier.

7. The method of claim 6 further comprising:

storing in the second radio node information to map a session identifier of the first access terminal to an Internet protocol address of the first radio network controller; and

using the stored information at the second radio node to determine the Internet protocol address of the first radio network controller using a session identifier included in an access channel message received from the first access terminal.

8. The method of claim 1 further comprising:

establishing, through the first radio node, a third session for a third access terminal on a selected one of either the first radio network controller or a second radio network controller.

9. The method of claim 8 further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller based at least on a loading of the first and second radio network controllers.

10. The method of claim 8 further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller based at least on the routing distance between the first radio node and the first and second radio network controllers.

11. The method of claim 2 further comprising:

employing a chassis-based hardware platform with multiple server cards to implement each of the first and second radio network controllers.

12. The method of claim 11 further comprising:

routing incoming packets to server cards based on session identifiers using an I/O card.

13. The method of claim 12 wherein the session identifiers comprise 1xEV-DO UATI.

14. The method of claim 1 further comprising:

establishing a first association between the first radio node and the first radio network controller, and

establishing a second association between the first radio node and the second radio network controller.

15. The method of claim 4 wherein the signaling occurs when the first access terminal moves towards any portion of the coverage area of the second radio node.

16. The method of claim 6 wherein the session identifier comprises a 1xEV-DO UATI.

17. The method of claim 7 further comprising:

encapsulating at least one of the access channel messages in an Internet protocol packet with a destination address equal to the Internet protocol address of the first radio network controller.

18. The method of claim 8 further comprising:

maintaining the third session on the selected one of either the first radio network controller or the second radio network controller as the third access terminal moves from the coverage area of the first radio node.

19. The method of claim 14 further comprising:

establishing a third association between the second radio node and the first radio network controller, and

establishing a fourth association between the second radio node and the second radio network controller.

20. The method of claim 2 wherein when the first access terminal is in the coverage area of the first radio node, data packets received at the first radio node on the first traffic channel from the first access terminal are sent to a network address of the first radio network controller over the network.

21. The method of claim 2 wherein when the first access terminal is in the coverage area of the first radio node, data packets destined for the first access terminal are sent by the first radio network controller to a network address of the first radio node over the network.

22. The method of claim 2 wherein when the second access terminal is in any portion of the coverage area of the second radio node, data packets received at the second radio node on the second traffic channel from the second access terminal are sent to a network address of the second radio network controller over the network.

23. The method of claim 2 wherein when the second access terminal is in any portion of the coverage area of the second radio node, data packets destined for the second access terminal are sent by the second radio network controller to a network address of the second radio node over the network.

24. The method of claim 2 wherein when the first access terminal is in any portion of the coverage area of the second radio node, data packets received at the second radio node from the first access terminal are sent to the network address of the first radio network controller over the network without traversing the second radio network controller.

25. The method of claim 2 wherein when the first access terminal is in any portion of the coverage area of the second radio node, data packets destined for the first access terminal are sent by the first radio network controller to the network address of the second radio node over the network without traversing the second radio network controller.

26. The method of claim 1, wherein the first radio node receives paging requests from more than one radio network controller.

27. The method of claim 1, wherein establishment of the first session follows powering on of the first access terminal and permits establishment of a first traffic channel between the first access terminal and the first radio network controller of the network when the first access terminal is no longer dormant.

28. The method of claim 1, wherein the first traffic channel is established in response to a connection request message sent by the first access terminal.

29. The method of claim 2, 1, 3, 4, 5, 6, or 7, wherein the first radio network controller comprises a default controller for the first radio node, the method further comprising:

routing, by the first radio node, data packets received from a third access terminal that does not have an existing session to the first radio network controller.

30. The method of claim 2 or 1, wherein the first or second radio node receives forward link traffic channel packets from more than one radio network controller.

31. The method of claim 2 or 1, wherein the first or second radio node sends reverse link traffic channel packets to more than one radio network controller.

32. The method of claim 2 or 1, wherein traffic channel radio resources are managed in the first and second radio nodes and the first or second radio network controller requests radio resources from the first or second radio node before adding any of its sectors to any traffic channel.

33. The method of claim 2 or 1, wherein the first and second radio network controllers reside in different locations and are connected by a metropolitan-area network.

34. The method of claim 1, 8 or 9, in which the first session is transferred from the first radio network controller in one subnetwork to another radio network controller in another subnetwork based upon a predetermined criterion.

35. The method of claim 34, wherein the session transfer is triggered by the first access terminal upon detection of a subnetwork change.

36. The method of claim 34, wherein the session transfer is triggered by a radio network controller.

37. The method of claim 2, 1, or 3 further comprising:

at the first radio network controller, selecting a packet data serving node to serve the first access terminal.

38. The method of claim 2 further comprising:

at the first radio network controller, using a mobility manager to maintain a current location information of the first access terminal.

39. The method of claim 8, 9, or 10 further comprising:

using an RNC resource control agent to assign sessions to the first and second radio network controllers.

40. The method of claim 39, wherein the RNC resource control agent resides on a separate server.

42. The method of claim 39 further comprising:

performing, by the RNC resource control agent, load balancing in assigning sessions to radio network controllers.

43. The method of claim 39, further comprising:

selecting, by the RNC resource control agent, a Previously Presented RNC in network-initiated dormant handoffs.

44. The method of claim 39, wherein the RNC resource control agent function is distributed among the radio network controllers and radio nodes, and the radio network controllers and the radio nodes continuously communicate resource information to each other to enable individual network nodes to make session assignment decisions on their own.

45. The method of claim 39, further comprising:

maintaining, by the RNC resource control agent, session information for all sessions under the RNC resource control agent'"'"'s control.

46. The method of claim 2, 5, or 8, wherein the radio network controllers also include a PDSN function.

47. The method of claim 46, wherein the PDSN function includes Simple IP, Mobile IP and AAA client functions.

48. The method of claim 46, 2, 5, or 8 wherein a radio network controller is co-located with a radio node.

49. The method of claim 35 wherein the subnetwork is a 1xEV-DO subnet.

41. The method of 2, 5, or 14, wherein each radio node in the radio access network is associated with a default radio network controller, the method further comprising:

determining, by an RNC resource control agent, an association between a radio node and its default radio network controller.

50. A method comprising:

enabling a radio node to simultaneously serve both a first access terminal and a second access terminal, the first access terminal having a first session established on a first radio network controller and the second access terminal having a second session established on a second radio network controller, the radio node being interconnected with the radio network controllers using a packet network, wherein the radio node is enabled to simultaneously serve both the first access terminal and the second access terminal when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

51. The method of claim 50 further comprising:

maintaining the first session on the first radio network controller as the first access terminal moves from a coverage area of the radio node.

52. The method of claim 50 further comprising:

maintaining the second session on the second radio network controller as the second access terminal moves from a coverage area of the radio node.

53. The method of claim 50 further comprising:

signaling between the first radio network controller and the second radio network controller.

54. The method of claim 50 further comprising:

routing access channel packets received from the first and second access terminals by determining an Internet protocol address of the respective radio network controllers.

55. The method of claim 54 wherein the Internet protocol address is determined using a session identifier.

56. The method of claim 55 further comprising:

storing in the radio node information to map a session identifier of the first access terminal to an Internet protocol address of the first radio network controller,

using the stored information at the radio node to determine the Internet protocol address of the first radio network controller using a session identifier included in an access channel message received from the first access terminal.

57. The method of claim 55 wherein the session identifiers comprise 1xEV-DO UATI.

58. The method of claim 50 further comprising:

establishing, through the radio node, a third session for a third access terminal on a selected one of either the first radio network controller or the second radio network controller.

59. The method of claim 58 further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller based at least on a loading of the first and second radio network controllers.

60. The method of claim 58 further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller based at least on the routing distance between the first radio node and the first and second radio network controllers.

61. The method of claim 50 further comprising:

establishing a first association between the first radio node and the first radio network controller, and

establishing a second association between the first radio node and the second radio network controller.

62. The method of claim 50 also comprising:

at the radio node,

routing access channel packets received from a third access terminal to a selected one of either the first radio network controller or the second radio network controller by determining an Internet protocol address of a serving radio network controller associated with the third access terminal.

63. The method of claim 62 wherein the Internet protocol address is determined using a session identifier.

64. The method of claim 63 wherein the session identifier comprises a 1xEV-DO UATI.

65. The method of claim 62 further comprising:

at the radio node, storing information to map a session identifier of the third access terminal to an Internet protocol address of the serving radio network controller.

66. The method of claim 62 further comprising:

encapsulating at least one of the access channel packets in an Internet protocol packet with a destination address equal to the Internet protocol address of the serving radio network controller.

67. The method of claim 62, further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller as the serving radio network controller based at least on a loading of the first and second radio network controllers.

68. The method of claim 67, wherein the selecting is performed when an access channel packet of the access channel packets comprises a 1xEV-DO Random Access Terminal Identifier (RATI).

69. The method of claim 62 further comprising:

selecting the selected one of either the first radio network controller or the second radio network controller as the serving radio network controller based at least on respective routing distances between the radio node and each of the first and second radio network controllers.

70. The method of claim 62 wherein the radio node receives forward link traffic channel packets from more than one radio network controller.

71. The method of claim 62 wherein the radio node sends reverse link traffic channel packets to more than one radio network controller.

72. The method of claim 62 wherein traffic channel radio resources are managed in the radio node, the radio node supports sectors, and the first or second radio network controller requests radio resources from the radio node before adding any of the radio node'"'"'s sectors to any traffic channel.

73. A system comprising:

a first radio network controller;

a second radio network controller; and

a first radio node interconnected with the first and second radio network controllers using a packet network, the first radio node enabled to simultaneously serve both a first access terminal and a second access terminal, the first access terminal having a first session established on a first radio network controller and the second access terminal having a second session established on a second radio network controller, wherein the first radio node is enabled to simultaneously serve both the first access terminal and the second access terminal when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

74. The system of claim 73 also comprising a second radio node, wherein:

the first and second radio nodes are each configured to receive data from and transmit data to each of the first and second access terminals when the respective access terminal is located in a coverage area associated with the respective radio node;

the first and second radio network controllers are each configured to receive data from and transmit data to the respective first and second access terminals through the first or second radio nodes; and

the packet network enables many-to-many communication among the first and second radio network controllers and the first and second radio nodes, wherein;

a first traffic channel is established between the first access terminal and the first radio network controller of the network through the first radio node when the first access terminal is in the coverage area of the first radio node,

a second traffic channel is established between the second access terminal and the second radio network controller of the network through the second radio node when the second access terminal is in the coverage area of the second radio node, and

the first traffic channel is maintained between the first access terminal and the first radio network controller without requiring the first traffic channel to pass through another radio network controller when the first access terminal moves from the coverage area of the first radio node to any portion of the coverage area of the second radio node.

75. The system of claim 74 wherein the network comprises an Internet protocol network.

76. The system of claim 75 wherein the first and second radio network controllers and the first and second radio nodes are associated with a single subnetwork.

77. The system of claim 73 further comprising:

a second radio node enabled to establish a third session for a third access terminal on a selected one of either the first radio network controller or the second radio network controller.

78. A method comprising:

in a radio access network, serving traffic channels between at least two access terminals and at least two different radio network controllers through a single radio node without regard to which portion of a coverage area of the radio node each of the at least two access terminals is located, wherein data packets between an access terminal of the at least two access terminals and a radio network controller of the at least two different radio network controllers do not traverse any other radio network controller, the single radio node being interconnected with the at least two radio network controllers using a packet network, and

maintaining a session on the radio network controller of the at least two different radio network controllers when the access terminal of the at least two access terminals moves from any portion of a coverage area of the single radio node to any portion of a coverage area of another radio node, wherein the session is maintained when the access terminal is dormant;

wherein when the access terminal is dormant, the access terminal has the session established on the radio network controller and does not have any traffic channel established with any radio network controller.

79. The method of claim 78, wherein the serving comprises:

maintaining a first traffic channel between the access terminal and the radio network controller when the access terminal moves from any portion of the coverage area of the single radio node to any portion of the coverage area of the another radio node.

80. The method of claim 78 further comprising:

signaling between the at least two different radio network controllers.

81. The method of claim 78 further comprising:

routing access channel packets received from the access terminal by determining an Internet protocol address of a serving radio network controller of the at least two different radio network controllers.

82. The method of claim 81 wherein the Internet protocol address is determined using a session identifier.

83. The method of claim 82 further comprising:

storing, in the single radio node, information to map the session identifier of the access terminal to the Internet protocol address of the serving radio network controller; and

using the stored information to determine the Internet protocol address of the serving radio network controller using the session identifier included in an access channel message received from the access terminal.

84. The method of claim 78 further comprising:

establishing, through the single radio node, another session for another access terminal of the at least two access terminals on a selected one of the at least two radio network controllers.

85. The method of claim 84 further comprising:

selecting the selected one of the at least two radio network controllers based at least on a loading of the at least two radio network controllers.

86. The method of claim 84 further comprising:

selecting the selected one of the at least two radio network controllers based at least on the routing distance between the radio node and the at least two radio network controllers.

87. The method of claim 84 wherein the session identifiers comprise 1xEV-DO UATI.

88. The method of claim 78 further comprising:

establishing a first association between the radio node and a first radio network controller of the at least two radio network controllers, and

establishing a second association between the radio node and a second radio network controller of the at least two radio network controllers.

89. A system comprising:

radio nodes;

radio network controllers; and

a packet network interconnecting the radio nodes and the radio network controllers;

the system enabling serving of traffic channels between at least two access terminals and at least two different radio network controllers through a single radio node without regard to which portion of a coverage area of the radio node each of the at least two access terminals is located, wherein data packets between a first access terminal of the at least two access terminals and a first radio network controller of the radio network controllers do not traverse any other radio network controller,

the system also enabling the first access terminal to maintain a first session on the first radio network controller when the first access terminal moves from any portion of the coverage area of the radio node to any portion of a coverage area of another radio node through which a second access terminal of the at least two access terminals has a second session on a second radio network controller of the radio network controllers, wherein the first access terminal is enabled to maintain the first session on the first radio network controller when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

90. A method comprising:

at a radio network controller in communication with a first radio node and a second radio node through a packet network that enables many-to-many communication,

establishing a first traffic channel with a first access terminal through the first radio node when the first access terminal is in a coverage area of the first radio node,

maintaining the first traffic channel with the first access terminal without requiring the first traffic channel to pass through another radio network controller when

(a) the first access terminal moves from a coverage area of the first radio node to any portion of a coverage area of the second radio node, and

(b) a second traffic channel exists between a second access terminal, in any portion of the coverage area of the second radio node, and a second radio network controller; and

establishing a first session for the first access terminal through the first radio node when the first access terminal is in the coverage area of the first radio node, and

maintaining the first session as the first access terminal moves from the coverage area of the first radio node;

wherein the first session is established and the first session is maintained when the access terminal is dormant; and

wherein when the first access terminal is dormant, the first access terminal has the first session established through the first radio node and does not have any traffic channel established with any radio network controller.

91. The method of claim 90 further comprising:

receiving an access channel message from the first access terminal through the second radio node.

92. An apparatus comprising:

means for establishing a first session with a first radio network controller for a first access terminal through a packet network that enables many-to-many communication and a first radio node when the first access terminal is in a coverage area of the first radio node, wherein the first session is established when the first access terminal is dormant, and

means for maintaining the first session as the first access terminal moves from the coverage area of the first radio node to any portion of a coverage area of a second radio node through which a second access terminal has a second session on a second radio network controller, wherein the first session is maintained when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

93. The apparatus of claim 92 also comprising:

means for establishing a first traffic channel through the first radio network controller with the first access terminal through the packet network and the first radio node when the first access terminal is in the coverage area of the first radio node, and

means for maintaining the first traffic channel with the first access terminal without requiring the first traffic channel to pass through another radio network controller when

(a) the first access terminal moves from the coverage area of the first radio node to any portion of a coverage area of a second radio node, and

(b) a second traffic channel exists between the second access terminal, in any portion of the coverage area of the second radio node, and the second radio network controller.

94. The apparatus of claim 92 further comprising:

means for receiving an access channel message from the first access terminal through the second radio node and the packet network.

95. An apparatus comprising:

means for enabling a radio node to simultaneously serve both a first access terminal and a second access terminal, the first access terminal having a first session established on a first radio network controller and the second access terminal having a second session established on a second radio network controller, the radio node being interconnected with the radio network controllers using a packet network, wherein the radio node is enabled to simultaneously serve both the first access terminal and the second access terminal when the first access terminal is dormant;

wherein when the first access terminal is dormant, the first access terminal has the first session established on the first radio network controller and does not have any traffic channel established with any radio network controller; and

wherein when the second access terminal is dormant, the second access terminal has the second session established on the second radio network controller and does not have any traffic channel established with any radio network controller.

96. The apparatus of claim 95 further comprising:

means for routing access channel packets received from a third access terminal to a selected one of either the first radio network controller or the second radio network controller, through a packet network enabling many-to-many communication, by determining an Internet protocol address of a serving radio network controller associated with the third access terminal.

97. The apparatus of claim 96 further comprising:

means for storing information to map a session identifier of the third access terminal to an Internet protocol address of the serving radio network controller.

98. The apparatus of claim 96 further comprising:

means for encapsulating at least one of the access channel packets in an Internet protocol packet with a destination address equal to the Internet address of the serving radio network controller.

99. The apparatus of claim 96 further comprising:

means for selecting the selected one of either the first radio network controller or the second radio network controller as the serving radio network controller based at least on a loading of the first and second radio network controllers.

100. The apparatus of claim 96 further comprising:

means for selecting the selected one of either the first radio network controller or the second radio network controller as the serving radio network controller based at least on respective routing distances between the radio node and each of the first and second radio network controllers.

101. The apparatus of claim 100 wherein the means for selecting comprises means for selecting the selected one of either the first radio network controller or the second radio network controller as the serving radio network controller in response to an access channel packet of the access channel packets that comprises a 1xEV-DO Random Access Terminal Identifier (RATI).