Mobil communication system for providing IP packet communications and method for routing IP packets

• US 6,731,621 B1
• Filed: 03/03/1999
• Issued: 05/04/2004
• Est. Priority Date: 06/04/1998
• Status: Expired due to Term

• Current Assignee: FIPA Frohwitter Intellectual Property AG
• Original Assignee: Hitachi, Ltd.
• Inventors: Shirai, Keisuke, Ouchi, Toshiya, Mizutani, Mika, Matsui, Susumu, Hirayama, Koji, Shibata, Haruo
• Primary Examiner(s): Maung, Nay
• Assistant Examiner(s): SOBUTKA, PHILIP
• Application Number:
  US09/261,181
• Time in Patent Office: 1,889 Days
• Field of Search: 370/331-401, 455/432, 455/433, 455/435, 455/446, 455/554, 455/556, 455/557, 455/435.1, 455/432.1, 455/432.3
• US Class Current: 370/338
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 61/106 across networks, e.g. mapping telephone numbers to data network addresses
• CPC Class Codes: H04W 40/20 based on geographic position or location
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 40/28 for reactive routing
• CPC Class Codes: H04W 40/32 for defining a routing cluster membership
• CPC Class Codes: H04W 40/36 due to handover
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 92/02 Inter-networking arrangements

Abstract

A plurality of packet gate ways (PGWS) are connected between a mobile communication system and an internet so that the corresponding IP subnetworks to those PGWs may be built. A visitor location register (VLR) operates to notify the PGW of location information of the mobile station (MS) and an IP address of a data terminal connected with the MS. If the notified IP address belongs to another IP subnetwork, the PGW notifies the corresponding PGW to that IP subnetwork of a fact that the local PGW is a destination. The PGW operates to manage the location information of the MS connected with the data terminal based on the notified content and perform the packet routing based on the managed content.

Claims

1. A mobile communication system comprising:

a plurality of devices each configuring a radio cell, and transmitting/receiving signals to/from mobile terminals;

a mobile switching center connected to a respective one of said plurality of devices;

a location register connected to said mobile switching center for managing location information of the respective mobile terminals; and

a plurality of packet gateways directly connected to an IP network which is separate from said mobile communication system,

wherein each of said devices is connected to one of said plurality of packet gateways,

wherein said location register is connected to the one packet gateway which is responsive to a mobile terminal whose location information is being managed by said location register, and

wherein each packet gateway, the device connected thereto, and the mobile terminal which transmits/receives a signal to/from that device form an IP subnetwork.

2. The system of claim 1, wherein each of said devices includes at least one base station for transmitting/receiving a signal to/from a mobile terminal and a network controller connected to the base station, for managing the base station.

3. The system of claim 1, wherein said location register includes means for notifying a packet gateway of the location information of a mobile terminal.

4. The system of claim 3, wherein said location register further includes means for notifying said packet gateway of an IP address possessed by said mobile terminal.

5. The system of claim 4, wherein each mobile terminal includes means for notifying said mobile switching center of identification information of the mobile terminal and an IP address of the mobile terminal,

wherein said mobile switching center includes means for notifying said location register of the identification information notified from the mobile terminal, the IP address and the location information indicating a service area of said device which transmits/receives to/from said mobile terminal, and

wherein said location register includes means for managing said identification information, said location information and said IP address notified from said mobile switching center in a corresponding manner to one another, and means for notifying the packet gateway connected to said location register of said location information and said IP address notified from said mobile switching center.

6. A mobile communication system comprising:

a plurality of devices each configuring a radio cell, and transmitting/receiving signals to/from mobile terminals;

a mobile switching center connected to a respective one of said plurality of devices;

a location register connected to said mobile switching center for managing location information of the respective mobile terminals; and

a plurality of packet gateways connected to an IP network outside said mobile communication system,

wherein each of said devices is connected to one of said plurality of packet gateways,

wherein said location register is connected to the one packet gateway which is responsive to a mobile terminal whose location information is being managed by said location register, and

wherein each packet gateway, the device connected thereto, and the mobile terminal which transmits/receives a signal to/from that device form an IP subnetwork,

wherein said location register includes means for notifying a packet gateway of the location information of a mobile terminal,

wherein said location register further includes means for notifying said packet gateway of an IP address possessed by said mobile terminal,

wherein each mobile terminal includes means for notifying said mobile switching center of identification information of the mobile terminal and an IP address of the mobile terminal,

wherein said mobile switching center includes means for notifying said location register of the identification information notified from the mobile terminal, the IP address and the location information indicating a service area of said device which transmits/receives to/from said mobile terminal, and

wherein said location register includes means for managing said identification information, said location information and said IP address notified from said mobile switching center in a corresponding manner to one another, and means for notifying the packet gateway connected to said location register of said location information and said IP address notified from said mobile switching center,

wherein each of said plurality of packet gateways comprises;

means for managing the IP address and the location information notified from a location register;

means, in a case where the IP address notified from said location register does not belong to the IP subnetwork containing the particular packet gateway, for notifying another packet gateway contained in the IP subnetwork to which said IP address belongs of said IP address and an IP address of the particular gateway;

means for managing the IP address notified from still another packet gateway and the IP address of said still another packet gateway;

means, in a case where a destination IP address of a received IP packet is managed to correspond to location information, for transferring the received IP packet to a mobile terminal possessing said destination IP address, via the device corresponding to said location information; and

means, in a case where a destination IP address of a received IP packet is managed to correspond to the IP address of another packet gateway, for transferring said received IP packet to said another packet gateway.

7. A packet gateway connected to a mobile communication network and directly connected to an IP network which is separate from said mobile communication network, said mobile communication network comprising:

at least one device for configuring a radio cell and transmitting/receiving a signal to/from a mobile terminal;

a mobile switching center connected to each device; and

a location register connected to said mobile switching center for managing location information of the mobile terminal,

wherein said packet gateway comprises;

a routing unit for connecting with another router on said IP network, and

a managing unit for controlling transfer of an IP packet to/from said IP network,

wherein said packet gateway further comprises;

an interface unit for connecting with each device and said location register, and

wherein said packet gateway, said at least one device, and the mobile terminal form an IP subnetwork which is connected to said routing unit and said interface unit.

8. A packet gateway connected to an IP network and a mobile communication network, said mobile communication network comprising:

at least one device for configuring a radio cell and transmitting/receiving a signal to/from a mobile terminal;

a mobile switching center connected to each device;

a location register connected to said mobile switching center for managing location information of the mobile terminal,

wherein said packet gateway comprises;

a routing unit for connecting with another router on said IP network, and

a managing unit for controlling transfer of an IP packet to/from said IP network,

wherein said packet gateway further comprises;

an interface unit for connecting with each device and said location register,

wherein said packet gateway, said at least one device, and the mobile terminal form an IP subnetwork which is connected to said routing unit and said interface unit; and

a memory for storing an IP address possessed by a data terminal connected to a mobile terminal contained in said IP subnetwork and location information indicating a service area of the device responsive to said mobile terminal in a corresponding manner to one another, said IP address being received by said interface unit from said location register,

wherein, in a case where a destination of an IP packet received by said routing unit or said interface unit is stored in said memory so as to correspond to the location information, said managing unit controls transfer of the received IP packet via said interface unit to the device corresponding to said location information.

9. The packet gateway of claim 8, wherein, in a case where the IP address received by said interface unit does not belong to an IP subnetwork containing said packet gateway, said managing unit connects with said IP network, and controls transmission of said IP address and an IP address of said packet gateway via said routing unit to another packet gateway contained in an IP subnetwork to which said IP address belongs.

10. The packet gateway of claim 8, wherein said packet gateway has a foreign agent function, and

wherein, in a case where an IP address received by said interface unit from said location register does not belong to an IP subnetwork containing said packet gateway, said managing unit controls transmission of an IP address of said packet gateway to a router having a home agent function on said IP network.

11. The packet gateway of claim 9, wherein said memory further stores the IP address received by said routing unit from another packet gateway and the IP address of said another packet gateway in a corresponding manner to one another, and

wherein, in a case where a destination of an IP packet received by said routing unit or said interface unit is stored in said memory so as to correspond to the IP address of another packet gateway, said managing unit controls transmission of the received IP packet via said routing unit to said another packet gateway.

12. A location information managing method in a communication system which includes a mobile communication system including at least one device for configuring a radio cell and transmitting/receiving a signal to/from a mobile terminal, a mobile switching center connected to each device, a location register connected to said mobile switching center for managing location information of the mobile terminal, and a packet gateway connected to said mobile communication system and directly connected to an IP network which is separate from said mobile communication system, said method comprising the steps of:

notifying, by said mobile switching center, said location register of an IP address possessed by the mobile terminal and location information indicating a service area of said at least one device which is responsive to said mobile terminal, said IP address being received from said mobile terminal,

wherein said packet gateway is connected to said location register and to each device;

notifying, by said location register, said packet gateway of said IP address and said location information; and

managing, by said packet gateway, said IP address and said location information in a correspondence manner to one another.

13. A location information managing method in a communication system which includes a mobile communication system including at least one device for configuring a radio cell and transmitting/receiving a signal to/from a mobile terminal, a mobile switching center connected to each device, a location register connected to said mobile switching center for managing location information of the mobile terminal, and a packet gateway connected to said mobile communication system and an IP network outside said mobile communication system, said method comprising the steps of:

notifying, by said mobile switching center, said location register of an IP address possessed by the mobile terminal and location information indicating a service area of said at least one device which is responsive to said mobile terminal, said IP address being received from said mobile terminal,

wherein said packet gateway is connected to said location register and to each device;

notifying, by said location register, said packet gateway of said IP address and said location information;

managing, by said packet gateway, said IP address and said location information in a correspondence manner to one another; and

in a case wherein said IP address does not belong to an IP subnetwork containing said packet gateway, said at least one device connected to said packet gateway and a mobile terminal which transmits/receives a signal to/from said device, notifying, by said packet gateway, another packet gateway contained in another IP subnetwork to which said IP address belongs of said IP address and an IP address of said packet gateway.

14. The method of claim 13, further comprising the steps of:

receiving, by said packet gateway from another packet gateway connected to said IP network, the IP address which is managed by said another packet gateway to correspond to location information and the IP address of said another packet gateway; and

managing said IP address and the IP address of said another packet gateway in a correspondence manner to one another.

15. A location information notifying method in a communication system which includes a mobile communication system including at least one device for configuring a radio cell and transmitting/receiving a signal to/from a mobile terminal, a mobile switching center connected to each device, a location register connected to said mobile switching center for managing location information of the mobile terminal, and a packet gateway connected to said mobile communication system and directly connected to an IP network separate from said mobile communication system, said method comprising the steps of:

notifying, by said mobile switching center, said location register of identification information of the mobile terminal and of location information indicating a server area of the device which is responsive to a mobile terminal,

wherein said packet gateway is connected to said location register and each device;

notifying, by said location register, a home location register of said mobile terminal of said identification information of said mobile terminal, and obtaining from said home location register an IP address corresponding to said identification information; and

notifying, by said location register, said packet gateway of said location information and said IP address thus obtained.