Low-cost radio access network enabling local switching

• US 20060251008A1
• Filed: 06/30/2005
• Published: 11/09/2006
• Est. Priority Date: 05/04/2005
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Nokia Corporation
• Inventors: Narayanan, Ram Gopal Lakshmi, Wu, Michael, Bansal, Rajesh Chandra, Alinikula, Petteri, Skarp, Mika
• Granted Patent: US 7,385,947 B2
• Time in Patent Office: Days
• US Class Current: 370/328
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

An access-point node to a first network cell of a radio access network, to an access-center node and to a radio access network enable local service providers in rural areas to provide mobile telecommunication at low cost for end users. The access-point node of the invention is configured to establish, maintain, and release a local user-data radio channel, which consists of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell. The access-point node is configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device and a third terminal device located outside the network cell. Link cost between the radio access network and the core network may be strongly reduced.

Claims

1. An access-point node to a network cell of a radio access network, the access-point node comprising:

a call-processing unit that is configured to ascertain whether an incoming communication request originates from an originating terminal device located inside the network cell and whether the incoming communication request is directed to the terminating terminal device located inside the network cell,

a local-switching unit that is connected with the call processing unit and configured to

establish, maintain, and release upon reception of a communication request originating and terminating inside the network cell a local user-data radio channel consisting of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell, and

establish, maintain, and release the first local channel section upon the reception of a communication request that is either originating from or terminating at the first terminal device inside the network cell, and a non-local-switching unit that is connected with the call-processing unit and configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device located in the network cell and a third terminal device located outside the network cell.

2. The access-point node of claim 1, wherein the call-processing unit is configured to generate and interpret control data directed to or received from the first or second terminal device and related to establishing, maintaining, or releasing the local user-data radio channel.

3. The access-point node of claim 1, which is further configured to exchange control data with the first or second terminal device through at least one control-data radio channel.

4. The access-point node of claim 1, having a first access database connected to the call-processing unit and comprising data related to terminal devices, which are permanently or temporarily registered to the access-point node.

5. The access-point node of claim 4, comprising a mobility-management unit connected to the first access database and the call-processing unit and configured to maintain the first access database.

6. The access-point node of claim 4, wherein the mobility-management unit further is configured to authenticate a requesting terminal device located in the network cell and requesting authentication, based on a successful validity check of an international-mobile-subscriber-identity (IMSI) value, in either the first access data base or a second access data base maintained at the access-center node.

7. The access-point node of claim 6, wherein the mobility-management unit is configured to

extract the IMSI value from an authentication request message received from the requesting terminal device,

ascertain whether the IMSI value is allocated to a registered terminal device held as permanently registered to the access-point node in the first access data base, and

generate and transmit a random number to the registered terminal device.

8. The access-point node of claim 7, wherein the mobility-management unit is configured to update an entry of the registered terminal device in the first access data base if the IMSI value is allocated to the registered terminal device registered to the access-point node.

9. The access-point node of claim 7, wherein the mobility-management unit is configured to

send a first control message to the access-center node indicating that an IMSI contained in the authentication request message received from the requesting terminal device is not contained in the first access database, wait for reception of a second control message from the access-center node indicating that the registered terminal device is registered with an external access-point node allocated to the access-center node, and

generate and transmit a random number to the registered terminal device after receiving the second control message.

10. The access-point node of claim 7, wherein the mobility-management unit is configured to use a preconfigured seed value in generating the random number for all terminal devices registered to the access-point node.

11. The access-point node of claim 7, wherein the mobility-management unit is configured to use the IMSI value of the registered terminal device as a seed value in generating the random number.

12. The access-point node of claim 7, wherein the mobility-management unit is further configured to store in the first access data base an entry allocated to the requesting terminal device requesting authentication, indicating that the requesting terminal device is currently in the coverage of the access-point node.

13. The access-point node of claim 7, wherein the mobility-management unit is configured to generate a control message for transmission to the access-center node, the control message indicating that the requesting terminal device is currently in a coverage of the access-point node.

14. The access-point node of claim 7, wherein the mobility-management unit is further configured to perform an additional authentication procedure according to a global system for mobile communication (GSM) standard, if the authentication is to be performed for a terminal devicethat is not permanently registered to the access-point node.

15. The access-point node of claim 4, wherein the mobility-management unit is configured to obtain from a terminal device within a coverage of the access-point node, upon request from the terminal device within a coverage of the access-point node or automatically after a predetermined time span following a last location update for the terminal device within a coverage of the access-point node, an IMSI value, a temporal-mobile-subscriber-identity (TMSI) value, and an international-mobile-equipment-identity (IMEI) value allocated to the terminal device within the coverage of the access-point node.

16. The access-point node of claim 15, wherein the mobility-management unit is configured to update a current location of the terminal device in the coverage of the access-point node in the first access data base.

17. The access-point node of claim 4, wherein the mobility-management unit is configured to extract an IMSI value of a terminal device from a location-update-request message, that is received from the terminal device.

18. The access-point node of claim 16, wherein the mobility-management unit is configured to

ascertain whether the IMSI value is allocated to a registered terminal device held as registered to the access-point node in the first access data base, send to the access-center node a third control message indicating that the IMSI value of the registered terminal device is not contained in the first access database,

wait for reception of a fourth control message from the access-center node indicating that the registered terminal device is registered with an external access-point node allocated to the access-center node, and

send to the terminal device a fifth control message indicating completion of a location update, if the IMSI value is contained in the first access data base or the fourth control message has been received from the access-center node.

19. The access-point node of claim 1, further comprising a clock-generation unit with a receiver wherein the clock-generation unit is configured to receive an external clock signal through a wireless channel, and which is configured to derive an internal clock signal from the external clock signal.

20. The access-point node of claim 1, wherein the call-processing and local-switching units are configured to perform signaling and call-switching functions for establishing, maintaining and releasing a local user-data channel according to a signaling system standard SS7.

21. The access-point node of claim 1, wherein the mobility-management unit is configured to packetize and send to the superordinate access-center node, control data received from the first terminal device in relation to a registration of the first terminal device with a core network connected with the access-point node.

22. The access-point node of claim 1, wherein the non-local switching unit comprises a packetizer that is configured to generate data packets according to an internet protocol (IP), the data packets including user data or control data.

23. The access-point node of claim 1, which is configured to interpret and generate control data according to a session initiation protocol, (SIP).

24. The access-point node of claim 1, which is configured to communicate with the access-center node through a wired communication channel.

25. The access-point node of claim 1, which is configured to communicate with the superordinate access-center node through a wireless communication channel.

26. An access-point module for implementation in a base transceiver station of a radio access network, the access-point module comprising:

a call-processing unit configured to ascertain whether an incoming communication request originates from an originating terminal device located inside a network cell and whether the incoming communication request is directed to a terminating terminal device located inside the network cell,

a local-switching unit configured to establish, maintain, and release a local user-data radio channel, consisting of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell, a non-local switching unit configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device and a third terminal device located outside the network cell, and

an interface unit connected with the call processing unit, the local-switching unit and the non-local switching unit and configured to connect with the base transceiver station and to exchange control data and user data with the base transceiver station.

27. The access-point module according to claim 26, which is formed by executable software embodied on a computer-readable medium.

28. The access-point module of claim 26, wherein the call-processing unit is configured to generate and interpret control data directed to or received from the first or second terminal device and related to establishing, maintaining, or releasing the local user-data radio channel.

29. An access-center node for providing communication between at least two assigned subordinate access-point nodes to network cells of a radio access network, or between an assigned subordinate access-point node and an assigned superordinate core-network node, the access-center node comprising:

a call-control unit configured to ascertain whether an incoming communication request originates from an originating terminal device in a network cell of an assigned subordinate access-point node and whether the incoming communication request is directed to a terminating terminal device located inside the network cell of the assigned subordinate access-point node,

a regional-switching unit connected to the call-control unit and configured to

exchange packetized user data and control data with an assigned subordinate first access-point node to a first network cell and with an assigned subordinate second access-point node to a second network cell to establish, maintain and release a predefined transmission capacity for a regional packet-switched user-data transmission path consisting of a first regional transmission path section having as endpoints the first access-point node and the access-center node, and further consisting of a second regional transmission path section having as endpoints the access-center node and the second access-point node, for establishing communication between a first terminal device located in the first network cell and a second terminal device located in the second network cell, and

a wide-area switching unit is connected to the call control unit and configured to exchange the packetized user data and control data with the first access-point node and with an assigned superordinate core network node in a core network for establishing, maintaining and releasing a wide-area user-data transmission path section consisting of the first regional transmission path section and a third regional transmission path section having as endpoints the access-center node and the core-network node.

30. The access-center node of claim 29, further comprising a second access database comprising data related to terminal devices that are permanently or temporarily registered to all assigned access-point nodes.

31. The access-center node of claim 30, further configured to maintain the second access database.

32. The access-center node of claim 30, which is configured to to receive a first control message from the first access-point node indicating that an international-mobile-subscriber-identity (IMSI) value contained in an authentication request message of a requesting terminal device is not contained in the first access database,

ascertain whether the IMSI value is allocated to a registered terminal device held as registered to one of the access-point nodes assigned to the access-center node, and

transmit a second control message to the access-point node, the second control message indicating that the registered terminal device is registered with a second access-point node allocated to the access-center node.

33. The access-center node of claim 32, which is further configured to store in the second access data base an entry allocated to the requesting terminal device requesting authentication, indicating that the requesting terminal device is currently in a coverage of the access-point node, which sent the first control message.

34. The access-center node of claim 31, which is further configured to receive from the assigned first access-point node a third control message indicating that an IMSI value of a terminal device, for which a location update procedure is being performed at the access-point node, is not contained the first access data base of the first access-point node, ascertain whether the IMSI value is allocated to a registered terminal device held as registered to one of the access-point nodes assigned to the access-center node, transmit a fourth control message to the first access-point node indicating that the registered terminal device is registered with a second access-point node allocated to the access-center node.

35. The access-center node of claim 34, which is further configured to send a sixth control message to the second access-point node requesting a validity status of the IMSI value received from the first access-point node, to wait for a seventh control message indicating the validity status, and to transmit the fourth control message to the first access-point node if the seventh control message indicates that the IMSI value is valid.

36. The access-center node of claim 33, which is further configured to send to a gateway node an eighth control message indicating a finding that the IMSI value of the registered terminal device is not contained in the second access data base,

wait for reception of a ninth control message from the gateway node indicating that the registered terminal device is registered with an external radio access network, and

send to the first access point node an tenth control message indicating the finding.

37. The access-center node of claim 29, which is configured to generate data packets according to an Internet protocol (IP), an individual data packet including either packetized user data or packetized control dataor both.

38. The access-center node of claim 29, which is configured to interpret and generate control data according to a session initiation protocol (SIP).

39. The access-center node of claim 29, which is configured to communicate with an assigned access-point node through a wired communication channel.

40. The access-center node of claim 29, which is configured to communicate with an assigned access-point node through a wireless communication channel.

41. The access-center node of claim 29, which is configured to communicate with an assigned gateway node through a wired communication channel.

42. The access-center node of claim 29, which is configured to communicate with an assigned gateway node through a wireless communication channel.

43. An access-center module for connection with a base transceiver station or a base station controller of a radio access network and for providing communication between at least two assigned subordinate access-point nodes to network cells of a radio access network or between one assigned subordinate access-point node and an assigned superordinate core network node, the access-point module configured to

ascertain whether an incoming communication request is directed to a terminal device located inside a network cell of an assigned subordinate access-point node,

exchange packetized user data and control messages with an assigned subordinate first access-point node to a first network cell and with an assigned subordinate second access-point node to a second network cell, establish, maintain and release a predefined transmission capacity for a regional packet-switched user-data transmission path consisting of a first regional transmission path section having as endpoints the first access-point node and the access-center node and of a second regional transmission path section having as endpoints the access-center node and the second access-point node, for establishing communication between a first terminal device located in the first network cell and a second terminal device located in the second network cell, and

exchange the packetized user data and control messages with the first access-point node and with an assigned superordinate gateway node of a core network for establishing, maintaining and releasing communication between the first terminal device located in the first network cell and a fourth terminal device located in a third network cell of a third access-point node, that is not assigned to the access-center node, or in a network cell outside a radio access network.

44. The access-center module according to claim 43, which is formed by executable software embodied on a computer-readable medium.

45. The access-center module of claim 43, further comprising a second access database comprising data related to terminal devices that are permanently or temporarily registered to all assigned access-point nodes.

68. The radio access network of claim 44, wherein the access-center node includes

a call-control unit configured to ascertain whether the incoming communication request originates from the originating terminal device in the network cell of an assigned subordinate access-point node and whether the incoming communication request is directed to the terminating terminal device located inside the network cell of the assigned subordinate access-point node, and whether the incoming communication request is directed to the terminating terminal device located inside the network cell of the assigned subordinate access-point node,

a regional switching unit connected to the call-control unit and configured to exchange packetized user data and control data with an assigned subordinate first access-point node to a first network cell and with an assigned subordinate second, access-point nodes to a second network cell to establish, maintain and release a predefined transmission capacity for a regional packetswitched user-data transmission path consisting of a first regional transmission path section having as end-points the first access-point and further consisting of a second regional transmission path section having as endpoints the access-center node and the second access-point node, ffor establishing communication between the first terminal device located in the first network cell and the second terminal device located in the second network device,

a wide-area switching unit is connected to the call control unit and configured to exchange the packetized user data and control data with the first access-point node and with an assigned superordinate core network node in a core network for establishing, maintaining and releasing a wide-area user-data transmission path section consisting of the first regional transmission path section and a third regional transmission path section having as endpoints the access-center node and the core-network node.

69. The radio access network of claim 68, wherein each access-point node is assigned to one of the access-center nodes.

48. A radio access network comprising:

a plurality of access-point nodes wherein at least one node of the plurality of access-point nodes includes

a call-processing unit that is configured to ascertain whether an incoming communication request originates from an originating terminal device located inside a network cell and-whether the incoming communication request is directed to a terminating terminal device located inside the network cell,

a local-switching unit that is connected with the call processing unit and configured to

establish, maintain, and release upon reception of a communication request originating and terminating inside the network cell a local user-data radio channel consisting of a first local channel section having as endpoints a first terminal device located in the network cell and the access-point node, and further consisting of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell, and

establish, maintain, and release the first local channel section upon the reception of a communication request that is either originating from or terminating at the first terminal device inside the network cell, and

a non-local-switching unit that is connected with the call-processing unit and configured to exchange packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device located in the network cell and a third terminal device located outside the network cell.

46. The radio access network of claim 48, having at least one access-center node for providing communication between at least two assigned subordinate access-point nodes to network cells of a radio access network, or between an assigned subordinate access-point node and an assigned superordinate core-network node,

and further comprising a protocol-mapping node, configured to communicate with a gateway node of a core network and with a second number of access-center nodes and

to translate control data of a first communication protocol used by a predetermined core-network node into session initiation protocol (SIP) control data, and to translate the SIP control data into control data of a first communication protocol.

47. The radio access network of claim 46, further comprising a home-location database node configured to communicate with an access-centernode according to the SIP and to store and provide to the access-center node permanent subscriber information allocated to each terminal-device address registered to the radio access network.

49. The radio access network of claim 48, further comprising a visitor-location database node configured to communicate with an access-centernode according to the SIP and to store and provide varying subscriber information allocated to each terminal-device address registered to the access network.

50. A method for providing wireless communication capability to a first terminal device located in a network cell of a radio access network, the method comprising the steps of:

ascertaining at an access-point node located in the network cell of the first terminal device whether an incoming communication request originates from the first terminal device and whether the incoming communication request is directed to the second terminal device located inside the network cell, upon reception of the communication request originating and terminating inside the network cell, establishing and maintaining a local user-data radio channel consisting of a first local channel section having as endpoints the first terminal device located in the network cell and the access-point node, and of a second local channel section having as endpoints the access-point node and a second terminal device located in the network cell, and

upon reception of a communication request originating from or terminating at the first terminal device inside the network cell,establishing and

maintaining the first local channel section, and exchanging packetized user data and control data with an assigned superordinate access-center node for establishing, maintaining and releasing communication between the first terminal device and a third terminal device located outside the network cell.

51. The method of claim 50, further comprising a step of exchanging control data between the access-point node and the first or second terminal device through at least one control-data radio channel for establishing, maintaining or releasing the local user-data radio channel.

52. The method of claim 50, comprising a step of maintaining a first access database located at the access-point node and comprising data related to terminal devices permanently or temporarily registered to the access-point node.

53. The method of claim 52, further comprising the steps of sending a request for authentication from a terminal device located in the network cell to the access-point node, and

performing a check of validity of the terminal device, wherein performing the check of validity comprises accessing the first access database or a second access database maintained at the access-center node.

54. The method of claim 53, wherein the step of sending the request for authentication comprises including an international-mobile-subscriber-identity (IMSI) value of the terminal device into the request, and which further comprises the steps of

extracting the IMSI value from the request for authentication at the access-point node,

ascertaining at the access-point node whether the IMSI value is allocated to a registered terminal device held as registered to the access-point node in the first access data base, and

generating and transmit a random number to the registered terminal device.

55. The method of claim 52, further comprising a step of performing an additional authentication procedure according to a (GSM) standard for a terminal device not held as permanently registered to the access-point node or an assigned superordinate access-center node.

56. The method of claim 53, further comprising the steps of

ascertaining whether an IMSI value is allocated to a registered terminal device held as permanently registered to the access-point node in the first access data base, and

sending to the access-center node a third control message indicating that the IMSI value of the registered terminal device is not contained in the first access data base,

waiting for reception of a fourth control message from the access-center node indicating that the registered terminal device is registered with an external access-point node allocated to the access-center node, and

sending to the registered terminal device a fifth control message indicating completion of a location update, if the IMSI value is contained in the first access data base or the fourth control message has been received from the access-center node.

57. The method of claim 50, further comprising steps of packetizing and sending to the access-center node control data received from the first terminal device in relation to a registration of the first terminal device with a core network connected with the access-point node.

58. The method of claim 50, further comprising using control messages according to a session initiation protocol, (SIP),

59. The method of claim 50, wherein providing wireless communication between the first terminal device and a third terminal device located in a coverage of a different access-point node further comprises

ascertaining at the access-center node that the incoming communication request originates from the first terminal device and that the incoming communication request is directed to a terminating terminal device located inside a network cell of another assigned subordinate access-point node, and

upon reception of a communication request originating and terminating in network cells of assigned subordinate first and second access-point nodes, exchanging packetized user data and control data with the first access-point node and with the second access-point node to establish, maintain and release a predefined transmission capacity for a regional packet-switched user-data transmission path consisting of a first regional transmission path section having as endpoints the first access-point node and the access-center node, and further consisting of a second regional transmission path section having as endpoints the access-center node and the second access-point node.

60. The method of claim 50, wherein providing wireless communication between the first terminal device and a fourth terminal device located outside the coverage of the access-center node further comprises

ascertaining at the access-center node that the incoming communication request involves the first terminal device and a fourth terminal device, and exchanging the packetized user data and control data with the first access-point node and with an assigned superordinate core network node in a core network for establishing, maintaining and releasing a wide-area user-data transmission path section consisting of a first regional transmission path section having as endpoints the first access-point node and the access-center node and a third regional transmission path section having as endpoints the access-center node and the core-network node.

61. The method of claim 59, wherein the ascertaining step comprises accessing a second access data base located at the access-center node and having data related to terminal devices permanently or temporarily registered to all access-point nodes assigned to the access-center node.

62. The method of claim 59, further comprising the steps of

receiving at the access-center node a first control message from the first access-point node indicating that an IMSI value contained in an authentication request message of a requesting terminal device is not contained in its first access database,

ascertaining whether the IMSI value is allocated to a registered terminal device held as registered to one of the access-point nodes assigned to the access-center node, and

transmitting a second control message to the access-point node, the second control message indicating that the registered terminal device is registered with a second access-point node allocated to the access-center node.

63. The method of claim 59, further comprising a step of storing in the second access data base an entry allocated to a requesting terminal device requesting authentication, indicating that the requesting terminal device is currently in a coverage of the access-point node, which sent the first control message.

64. The method of claim 59, further comprising the steps of

receiving at the access-center node from an assigned first access-point node a third control message indicating that an IMSI value of a terminal device, for which a location update procedure is being performed at the access-point node, is not contained in the first access data base, ascertaining at the access-center node that the IMSI value is allocated to a registered terminal device held as registered to one of the access-point nodes assigned to the access-center node, and

transmitting a fourth control message to the first access-point node indicating that the registered terminal device is registered with a second access-point node allocated to the access-center node.

65. The method of claim 64, further comprising the steps of

sending a sixth control message to the second access-point node requesting a validity status of the IMSI value received from the first access-point node, waiting for a seventh control message indicating the validity status, and

transmitting the fourth control message to the first access-point node only if the seventh control message indicates that the IMSI value is valid.

66. The method of claim 65, further comprising the steps of

sending to a gateway node an eighth control message indicating that the IMSI value of a terminal device is not contained in the second access data base,

waiting for reception of a ninth control message from the gateway node indicating that the registered terminal device is registered with an external radio access network, and

sending to the first access-point an tenth control message indicating the terminal device is not contained in the second access database.

67. The method of claim 60, wherein exchanging the packetized control data and exchanging the packetized user data between an access-point node and the access-center node, and between the access-center node and the core-network node comprises generating data packets according to an internet protocol(IP), wherein an individual data packet inclues the packetized user data or the packetized control data.