Protocol terminating method, control signal terminating server apparatus, and mobile communication system

• US 20050085227A1
• Filed: 08/27/2004
• Published: 04/21/2005
• Est. Priority Date: 09/10/2003
• Status: Active Grant

• Current Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Original Assignee: NTT Docomo Incorporated (Nippon Telegraph and Telephone Corporation)
• Inventors: Kakishima, Jun, Hirata, Shoichi, Yabusaki, Masami, Nishimura, Kenji
• Granted Patent: US 7,142,859 B2
• Time in Patent Office: Days
• US Class Current: 455/428
• CPC Class Codes: H04W 36/00695 using split of the control plane or user plane
• CPC Class Codes: H04W 36/10 Reselecting an access point controller
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 36/185 using make before break

Abstract

In a mobile communication network comprised of a plurality of switching devices and a plurality of base stations connected to the switching devices, while a mobile terminal to wirelessly communicate with the base stations is in a communication by a soft handover, a terminal endpoint of a protocol for control of the soft handover is relocated in changing a switching device to another as a branch/combining point of data on a communication route of the communication.

Claims

1. A protocol terminating method in a mobile communication network comprising a plurality of switching devices and a plurality of base stations connected to the switching devices,

wherein, while a mobile terminal to wirelessly communicate with the base stations is in a communication by a soft handover, a terminal endpoint of a protocol for control of the soft handover is relocated in changing a switching device to another as a branch/combining point of data on a communication route of the communication.

2. The protocol terminating method according to claim 1, wherein, where it is noted as to protocols for control of user data that a switching device at an uppermost point among the switching devices as branch/combining points on a routing path of the user data is defined as an upper MP(U) and that each switching device as a branch/combining point except for the upper MP(U) is defined as a lower MP(U),

the protocols for the control of the user data are terminated as follows:

a frame protocol is terminated between the upper MP(U) and a base station, between the upper MP(U) and a lower MP(U), between the lower MP(U) and another lower MP(U), and between the lower MP(U) and the base station;

each of protocols of MAC, RLC, and PDCP is terminated between the mobile terminal and the upper MP(U).

3. The protocol terminating method according to claim 2, wherein the mobile communication network comprises a control signal terminating server apparatus for terminating protocols for transmission/reception of control signals for the control of the soft handover,

wherein, where it is noted as to the protocols for transmission/reception of the control signals that a switching device at an uppermost point among branch/combining points on a routing path of the control signals is defined as an upper MP(C) and that each switching device as a branch/combining point except for the upper MP(C) is defined as a lower MP(C),

the protocols for the transmission/reception of the control signals are terminated as follows:

the frame protocol is terminated between the upper MP(C) and the base station, between the upper MP(C) and a lower MP(C), between the lower MP(C) and another lower MP(C), and between the lower MP(C) and the base station;

each of the protocols of MAC and RLC is terminated between the mobile terminal and the upper MP(C);

RRC is terminated in a section from the mobile terminal via the upper MP(C) to the control signal terminating server apparatus;

RNSAP is terminated between the upper MP(C) and the lower MP(C), between the lower MP(C) and another lower MP(C), between the upper MP(U) and the lower MP(U), and between the lower MP(U) and another lower MP(U);

NBAP is terminated between the upper MP(C) and the base station, between the lower MP(C) and the base station, between the upper MP(U) and the base station, and between the lower MP(U) and the base station.

4. The protocol terminating method according to claim 3, wherein a section between the control signal terminating server and the upper MP(C) and a section between the control signal terminating server and the upper MP(U) are terminated by a new communication protocol.

5. A control signal terminating server apparatus for terminating protocols for transmission/reception of control signals for a soft handover control,

in a mobile communication network comprising a plurality of switching devices and a plurality of base stations connected to the switching devices,

wherein, while a mobile terminal to wirelessly communicate with the base stations is in a communication by said soft handover, a terminal endpoint of a protocol for control of the soft handover is relocated in changing a switching device to another as a branch/combining point of data on a communication route of the communication.

6. A mobile communication system comprising a plurality of switching devices and a plurality of base stations connected to the switching devices, the mobile communication network comprising:

changing means for, while a mobile terminal to wirelessly communicate with the base stations is in a communication by a soft handover, changing a switching device to another as a branch/combining point of data on a communication route of the communication; and

protocol terminal endpoint relocating means for relocating a terminal point of a protocol for control of the soft handover, in the changing by the changing means.

7. The mobile communication system according to claim 6, where it is noted as to protocols for control of user data that a switching device at an uppermost point among the switching devices as branch/combining points on a routing path of the user data is defined as an upper MP(U) and that each switching device as a branch/combining point except for the upper MP(U) is defined as a lower MP(U),

the protocol terminal endpoint relocating means terminates the protocols for the control of the user data as follows:

the protocol terminal endpoint relocating means terminates a frame protocol between the upper MP(U) and a base station, between the upper MP(U) and a lower MP(U), between the lower MP(U) and another lower MP(U), and between the lower MP(U) and the base station;

the protocol terminal endpoint relocating means terminates each of protocols of MAC, RLC, and PDCP between the mobile terminal and the upper MP(U).

8. The mobile communication system according to claim 7, wherein the mobile communication network comprises a control signal terminating server apparatus for terminating protocols for transmission/reception of control signals for the soft handover control,

wherein, where it is noted as to the protocols for transmission/reception of the control signals that a switching device at an uppermost point among branch/combining points on a routing path of the control signals is defined as an upper MP(C) and that each switching device as a branch/combining point except for the upper MP(C) is defined as a lower MP(C),

the protocol terminal endpoint relocating means terminates the protocols for transmission/reception of the control signals as follows:

the protocol terminal endpoint relocating means terminates the frame protocol between the upper MP(C) and the base station, between the upper MP(C) and a lower MP(C), between the lower MP(C) and another lower MP(C), and between the lower MP(C) and the base station;

the protocol terminal endpoint relocating means terminates each of the protocols of MAC and RLC between the mobile terminal and the upper MP(C);

the protocol terminal endpoint relocating means terminates RRC in a section from the mobile terminal via the upper MP(C) to the control signal terminating server apparatus;

the protocol terminal endpoint relocating means terminates RNSAP between the upper MP(C) and the lower MP(C), between the lower MP(C) and another lower MP(C), between the upper MP(U) and the lower MP(U), and between the lower MP(U) and another lower MP(U);

the protocol terminal endpoint relocating means terminates NBAP between the upper MP(C) and the base station, between the lower MP(C) and the base station, between the upper MP(U) and the base station, and between the lower MP(U) and the base station.

9. The mobile communication system according to claim 8, wherein the protocol terminal endpoint relocating means terminates a section between the control signal terminating server and the upper MP(C) and a section between the control signal terminating server and the upper MP(U) by a new communication protocol.