Mobile communication system and method for transmission of connection less packets

• US 6,647,264 B1
• Filed: 09/23/1999
• Issued: 11/11/2003
• Est. Priority Date: 09/24/1998
• Status: Expired due to Fees

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation
• Inventors: Sasamoto, Yoshifumi
• Primary Examiner(s): Vo, Nguyen T.
• Assistant Examiner(s): Orgad, Edan
• Application Number:
  US09/401,283
• Time in Patent Office: 1,510 Days
• Field of Search: 455/433, 455/435, 455/445, 455/517, 455/560, 455/458, 455/466, 455/422, 455/561, 455/550, 455/432, 370/328, 370/329, 370/349, 370/353, 370/352-356, 370/401, 370/432, 370/351, 370/400, 370/431
• US Class Current: 455/445
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like

Abstract

In a mobile communication system, a gateway is connected to a connectionless data network for receiving a series of packets of same destination. A number of routers are connected to the gateway and a number of wireless access networks are connected respectively to the routers for establishing wireless links with mobile stations. The gateway is arranged to transmit a request message to all of the routers in response to receipt of the packet of first arrival from the data network to request a search for a mobile station specified by the packet. Each of the routers includes a memory for storing location data of mobile stations. Each router makes a search through its own memory in response to the request message, and responds with a reply message to receive the packets of first and second arrival from the gateway if the specified mobile station is found in the memory, and routes the received packets via the corresponding wireless access network to the mobile station.

Claims

1. A mobile communication system comprising:

a gateway connected to a connectionless data network;

a plurality of routers connected to said gateway; and

a plurality of wireless access networks, connected respectively to said routers, for establishing wireless links with mobile stations,

said gateway transmitting a request message to all of said routers in response to a packet from the connectionless data network for requesting a search for a mobile station specified by the packet,

each of said routers including a memory for storing location data of mobile stations, making a search through said memory in response to said request message, responding with a reply message to the gateway if the specified mobile station is found in said memory, receiving said packet from the gateway only if the specified mobile station is found in said memory, and routing the received packet via the corresponding wireless access network to the mobile station.

2. The mobile communication system of claim 1, wherein said gateway is arranged to:

receive a series of packets of same destination from the connectionless data network, and

transmit said request message to all of said routers in response to the packet of first arrival for requesting a search for a mobile station specified by the packet of first arrival and sequentially transmitting the received packets to one of the routers which responds with a reply message,

each of said routers is arranged to respond to said request message with said reply message to receive said packets if the specified mobile station is found in said memory, and

route the received packets via the corresponding wireless access network to the specified mobile station.

3. The mobile communication system of claim 2 wherein each of said routers is arranged to transmit a paging message to the corresponding wireless access network if the specified mobile station is not found in said memory for requesting a reply from the specified mobile station.

4. The mobile communication system of claim 2, wherein the reply message contains data necessary for routing said packet to one of said routers, and wherein said gateway includes a memory for receiving said data from each of said routers and storing the received data in the memory, said gateway routing a packet received from said data network according to the data stored in the memory.

5. The mobile communication system of claim 2, wherein the data stored in the memory of each of said routers contains an IP (Internet Protocol) address of the specified mobile station.

6. The mobile communication system of claim 2, wherein each of said wireless access networks comprises a group of cell-site base stations connected to a corresponding one of said routers to establish said wireless links with mobile stations located within coverage areas of the base stations.

7. The mobile communication system of claim 1, wherein said gateway is arranged to:

receive a series of packets of same destination from the connectionless data network,

transmit a request message to all of said routers in response to receipt of the packet of first arrival for requesting a search for a mobile station specified by the packet of first arrival,

transmit the packet of first arrival to one of the routers which responds with a reply message,

transmit the packet of second arrival to the responding router if the packet of second arrival is received before a predetermined time interval expires, and

transmit a disconnect signal to the responding router if said predetermined time interval expires after the transmission of each of the packets of first and second arrival,

each of said routers is arranged to;

respond to said request message with said reply message if the specified mobile station is found in said memory to receive the packets of first and second arrival and establish a connection to the specified mobile station via the corresponding wireless access network, and

transmit the received packets to the specified mobile station over the established connection, and

clear said connection in response to said disconnect signal.

8. The mobile communication system of claim 7, wherein each of said routers is arranged to transmit a paging message to the corresponding wireless access network if the specified mobile station is not found in said memory for requesting a reply from the specified mobile station.

9. The mobile communication system of claim 7, wherein the reply message contains data necessary for routing said packet to one of said routers, and wherein said gateway includes a memory for receiving said data from each of said routers and storing the received data in the memory, said gateway routing a packet received from said data network according to the data stored in the memory.

10. The mobile communication system of claim 7, wherein the data stored in the memory of each of said routers contains an IP (Internet Protocol) address of the specified mobile station.

11. The mobile communication system of claim 7, wherein each of said wireless access networks comprises a group of cell-site base stations connected to a corresponding one of said routers to establish said wireless links with mobile stations located within coverage areas of the base stations.

12. The mobile communication system of claim 1, wherein each of said routers is arranged to transmit a paging message to the corresponding wireless access network if the specified mobile station is not found in said memory for requesting a reply from the specified mobile station.

13. The mobile communication system of claim 1, wherein the reply message contains data necessary for routing said packet to one of said routers, and wherein said gateway includes a memory for receiving said data from each of said routers and storing the received data in the memory, said gateway routing a packet received from said data network according to the data stored in the memory.

14. The mobile communication system of claim 1, wherein the data stored in the memory of each of said routers contains an IP (Internet Protocol) address of the specified mobile station.

15. The mobile communication system of claim 1, wherein each of said wireless access networks comprises a group of cell-site base stations connected to a corresponding one of said routers to establish said wireless links with mobile stations located within coverage areas of the base stations.

16. The mobile communication system of claim 15, wherein said gateway is co-located with a mobile switching center which is connected to a public switched telephone network.

17. The mobile communication system of claim 16, wherein each of said routers is co-located with a base station controller which is connected to said mobile switching center.

18. A method of communication for a system comprising a gateway connected to a connectionless data network, a plurality of routers connected to said gateway, and a plurality of wireless access networks, connected respectively to said routers, for establishing wireless links with mobile stations, each of said routers including a memory for storing location data of mobile stations, the method comprising the steps of:

a) receiving a packet of first arrival from the connectionless data network at said gateway;

b) transmitting a request message from said gateway to all of said routers in response to receipt of the packet for requesting a search for a mobile station specified by the packet of first arrival;

c) making a search through the memory of each of the routers in response to said request message from the gateway;

d) receiving, at one of said routers, said packet from the gateway if the specified mobile station is found in the memory of said one router; and

e) routing the received packet via the corresponding wireless access network to the mobile station.

19. The method of claim 18, wherein the step (c) comprises the step of transmitting a paging message from said one router to the corresponding wireless access network if the specified mobile station is not found in the memory of said one router for requesting a reply from the specified mobile station.

20. A method of communication for a system comprising gateway connected to a connectionless data network, a plurality of routers connected to said gateway, and a plurality of wireless access networks, connected respectively to said routers, for establishing wireless links with mobile stations, each of said routers including a memory for storing location data of mobile stations, the method comprising the steps of:

a) receiving, at said gateway, packets of first and second arrival of same destination from the connectionless data network;

b) transmitting a request message from said gateway to all of said routers in response to receipt of the packet of first arrival for requesting a search for a mobile station specified by the packet of first arrival;

c) making a search through the memory of each of the routers in response to said request message from the gateway;

d) transmitting a reply message from one of said routers to said gateway if the specified mobile station is found in the memory of said one router;

e) transmitting said packets from the gateway to said one router in response to said reply message; and

f) receiving, at said one router, said packets from the gateway and routing the received packets via the corresponding wireless access network to the mobile station.

21. The method of claim 20, wherein the step (c) comprises the step of transmitting a paging message from said one router to the corresponding wireless access network if the specified mobile station is not found in the memory of said one router for requesting a reply from the specified mobile station.

22. A method of communication for a system comprising a gateway connected to a connectionless data network, a plurality of routers connected to said gateway, and a plurality of wireless access networks, connected respectively to said routers, for establishing wireless links with mobile stations, each of said routers including a memory for storing location data of mobile stations, the method comprising the steps of:

a) receiving, at said gateway, packets of first and second arrival of same destination from the connectionless data network;

b) transmitting a request message from said gateway to all of said routers in response to receipt of the packet of first arrival for requesting a search for a mobile station specified by the packet;

c) making a search, at each of said routers, through the memory of the router in response to said request message and transmitting a reply message back to said gateway from one of the routers if the specified mobile station is found in the memory of said one router and establishing a connection from said one router to the specified mobile station via the corresponding wireless access network;

d) transmitting, from the gateway to said one router, the packet of first arrival in response to said reply message;

e) transmitting, from the gateway to said one router, the packet of second arrival if the packet of second arrival is received before a predetermined time interval expires;

f) transmitting, from the gateway to said one router, a disconnect signal if said predetermined time interval expires after the transmission of each of the packets of first and second arrival;

g) transmitting said packets of first and second arrival from said one router to the specified mobile station over the established connection; and

h) clearing said connection in response to said disconnect signal.

23. The method of claim 22, wherein the step (c) comprises the step of transmitting a paging message from said one router to the corresponding wireless access network if the specified mobile station is not found in the memory of said one router for requesting a reply from the specified mobile station.