Arrangement and a Method in Communication Networks

• US 20080316980A1
• Filed: 08/28/2004
• Published: 12/25/2008
• Est. Priority Date: 08/28/2004
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Winell, Staffan, Lundin, Niklas Sven, Ahlen, Anders
• Granted Patent: US 8,018,909 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 36/12 Reselecting a serving backbone network switching or routing node
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management

Abstract

The present invention relates to an arrangement comprising a functional server node forming part of a conglomerate, or pool, of functional server nodes in common controlling a number of radio network control means, each functional server node being able to control any, or a number of, radio network control means, to which mobile stations are connected. The functional server nodes support transfer/redistribution of mobile stations between each other without interrupting the connection of the mobile stations, a target functional server node, to which it has been decided that a mobile station is to be transferred from a current functional server node, generates an area update or transfer acceptance message comprising an identification of the current functional server node, an identification of the target functional server node and a transfer indications. The invention also relates to a method of redistributing or transferring mobile station contexts.

Claims

1-33. -33. (canceled)

34. An arrangement comprising functional server nodes forming part of a conglomerate, or pool, of functional server nodes in common controlling a number of radio network control means, each functional server node being able to control any, or a number of, radio network control means, to which mobile stations are connected, characterized in that

the functional server nodes support transfer/redistribution of mobile stations or mobile station contexts between each other without interrupting the connection of the mobile station, and comprise message control means and in that when a mobile terminal station is to be moved from a first, current, functional server node to a second, target, functional server node, the message control means of said first, current, functional server node are adapted to generate an area update or transfer acceptance message comprising an identification of the first, current, functional server node, an identification of the second, target, functional server node and a transfer indication, and to send said area update or transfer acceptance message to the mobile station.

35. An arrangement according to claim 34, characterized in that

further a timer is included and set to a second, low, value in said area update or transfer acceptance message, the lapsing of which being adapted to serve as an indication to the mobile station that the mobile station should be adapted to send an (e.g. periodic) area updating request, and in that said, e.g. periodic, area updating request is adapted to be routed to the second, target, functional server node.

36. An arrangement according to claim 35, characterized in that

the functional server nodes comprise means for detecting, from a received, e.g. periodic, area update request message from a mobile station that the mobile station should be transferred and for extracting the identification of the current functional server node.

37. An arrangement according to claim 36, characterized in that

The second, target, functional server node is adapted to send an area updating acceptance message in response to the (periodic) area update request message from the mobile station, resetting the timer to a first value, indicating a longer time period than said second timer value.

38. An arrangement according to claim 34, characterized in that

the area or transfer acceptance message comprises a Routing Area Update (RAU) accept message comprising (P-)TMSI for the mobile station.

39. An arrangement according to claim 34, characterized in that

the identification of the first, current, functional server node comprises the Network Resource Identifier (NRI) of said first node and in that the identification of the second, target, functional server node comprises the Network Resource Identifier (NRI) of said second, target, node.

40. An arrangement according to claim 39, characterized in that

for the NRI of the target functional server node the conventional position in the (P-) TMSI is adapted to be used whereas for the NRI of the first, current, functional server node a new position in the (P-) TMSI is adapted to be used.

41. An arrangement according to claim 34, characterized in that

the transfer indication comprises a bit setting indication in (P-) TMSI adapted to indicate that the mobile station should be moved, e.g. due to a. decision taken in, or externally of, the first, current, functional server node.

42. An arrangement according to claim 34, characterized in that

the timer comprises a periodic RAU timer.

43. An arrangement at least according to claim 38, characterized in that

a Routing Area Update (RAU) Request received from a mobile station in the current functional server node is adapted to enable or trigger the taking of a decision as to transfer of the mobile station to another, target, functional server node.

44. An arrangement according to claim 43, characterized in that

the RAU request is a periodic RAU request.

45. An arrangement according to claim 34, characterized in that

the functional server nodes of a conglomerate or a pool are responsible for all or for a dedicated part of the radio networks, the radio network control means comprising one or more radio network control nodes (RNC, BSC) for each radio network.

46. An arrangement according to claim 34, characterized in that

the functional server nodes comprise packet data support nodes comprising SGSN/CGSN nodes divided into functional SGSN/CGSN server nodes and functional user gateway nodes, e.g. media gateway nodes (MGW) or SGSN/CGSN nodes with control and user plane functionalities integrated, or MCSs.

47. An arrangement according to claim 34, characterized in that

the radio networks are UTRANs or BSSs and in that the radio network control means comprises one or more RNCs/BSCs.

48. An arrangement according to claim 34, characterized in that

decision control means are provided for determining whether a mobile terminal station is to be transferred from a current functional server node to another, target, functional server node within the pool or conglomerate, said control means being externally provided in relation to the functional server node, e.g. provided on the O&

M level, manually or automatically operated, or that the control means comprises a pool/conglomerate supervising arrangement, or that the control means are provided in the functional server node.

49. An arrangement according to claim 48, characterized in that

the control means comprises shared radio network control means.

50. An arrangement according to claim 34, characterized in that

the functional server node acting as a target node is adapted to use the requesting, current functional server node identification, e.g. NRI, for context request messages (e.g. SGSN Context Request Messages).

51. An arrangement according to claim 34, characterized in that

it is adapted to be used in a GSM/GPRS communications system.

52. An arrangement according to claim 34, characterized in that

it is adapted to be used in UMTS.

53. An arrangement according to claim 34, characterized in that

a current functional server node is adapted to request transfer of one, more or all mobile terminal stations connected to it.

54. An arrangement according to claim 53, characterized in that

It is adapted to implement scheduled transfer.

55. An arrangement according to claim 53, characterized in that

For transfer of a plurality of mobile terminal stations, means are adapted to be responsible for requesting transfer to several, different target functional server nodes in order to assist in load sharing among functional server nodes.

56. A functional server node forming part of a conglomerate, or pool, of functional server nodes in common controlling a number of radio network control means, said functional server node being able to control any, or a number of, radio network control means, to which mobile terminal stations are connected, characterized in that

it is adapted to support transfer/redistribution of mobile stations or mobile station contexts to/from other functional server nodes without the connection of the mobile stations being interrupted, that it comprises decision control means for receiving, or generating, a decision to transfer a mobile station to another, target, functional server node, message control means for, when a transfer decision is received/taken, generating an area update or transfer acceptance message comprising an identification of said current functional server node itself, an identification of the target functional server node and a transfer indication, and for sending said message to the mobile station, and in that it further comprises means for detecting such a message from another functional server node in its function as a target functional server node.

57. A functional server node according to claim 56, characterized in that

the message control means comprises means for setting a timer, lapse of said timer being adapted to activate or trigger the sending of a (periodic) area updating request, which e.g. is a periodic area updating request, from the mobile station to the target functional server node.

58. A functional server node according to claim 56, characterized in that

it comprises an SGSN, a CGSN comprising the functionalities of an SGSN and a GGSN, in a split or monolithic architecture, or an MSC.

59. A functional server node according to any one of claim 56, characterized in that

the area or transfer acceptance message comprises a Routing Area Update (RAU) accept message comprising (P-) TMSI for the mobile station.

60. A functional server node according to claim 59, characterized in that

the identification of the first, current, functional server node comprises the Network Resource Identifier (NRI) of said first node and in that the identification of the second, target, functional server node comprises the Network Resource Identifier (NRI) of said second, target, node.

61. A functional server node according to claim 59, characterized in that

the transfer indication comprises a bit setting in (P-) TMSI indicating that the mobile station should be moved, e.g. due to a decision taken in or externally of, the first, current, functional server node.

62. A method for transferring a number of mobile station contexts from a current functional server node forming part of a conglomerate or a pool of functional server nodes in common controlling a number of radio network control means, wherein each functional server node is able to control any, or a number of, radio network control means, to another, target, functional server node of the conglomerate/pool, characterized in that it comprises the steps of:

receiving an area updating request from a mobile station within the pool/conglomerate area in a first, current, functional server node;

generating, or receiving, in the current functional server node, a decision to transfer the mobile terminal station to another, target, functional server node,

generating, in the current functional server node, an area update or transfer acceptance message comprising an identification of the current functional server node, an identification of the second target functional server node, and a transfer indication, setting a timer to a given value,

sending the area update or transfer acceptance message to the mobile station,

sending of an area updating request including the information of the area update or transfer acceptance message from the mobile station upon lapse of the timer to the target functional server node using the identification thereof in the area update or transfer acceptance message, or

awaiting a message relating to a predetermined relevant action taken by the mobile station, e.g. a RAU, an attach request, a LAU,

sending an information request from the target functional server node to the current functional server node using the identification information received in the area updating request or other message relating to a predetermined action from the mobile station,

returning an information response to the target, or second, functional server node,

returning a transfer acceptance from the target functional server node to the mobile station.

63. A method according to claim 62, characterized in that

the functional server nodes comprises SGSNs or CGSNs in a monolithic architecture or SGSN or CGSN server means in a split architecture.

64. A method according to claim 62, characterized in that

the identification information comprises NRI both of the current and the target functional server nodes respectively, that the acceptance message comprises a RAU accept message and that the information request comprises a SGSN Context Request and in that the information response comprises an SGSN Context Response.

65. A method according to claim 62, characterized in that

the functional server nodes comprises MSCs.

66. A method according to claim 62, characterized in that

it is used in a system comprising a number of operators sharing at least some Radio Networks/Radio Network Control means (RNC, BSC)