Optimum routing system

• US 6,400,722 B1
• Filed: 08/24/1998
• Issued: 06/04/2002
• Est. Priority Date: 10/14/1997
• Status: Expired due to Fees

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Rai, Girish, Chuah, Mooi
• Primary Examiner(s): Olms, Douglas
• Assistant Examiner(s): Pizarro, Ricardo M.
• Application Number:
  US09/138,683
• Time in Patent Office: 1,380 Days
• Field of Search: 370/401, 370/402, 370/351, 370/466, 370/468, 370/522, 370/524, 370/410, 370/467, 370/359, 370/419, 370/465, 370/400, 370/353, 370/462, 370/229, 370/230, 709/229, 709/225, 709/224, 709/250, 445/436, 445/445, 445/432
• US Class Current: 370/401
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/161 Implementation details of TCP/IP or UDP/IP stack architecture; Specification of modified or new header fields
• CPC Class Codes: H04L 69/164 Adaptation or special uses of UDP protocol
• CPC Class Codes: H04L 69/168 specially adapted for link layer protocols, e.g. asynchronous transfer mode [ATM], synchronous optical network [SONET] or point-to-point protocol [PPP]
• CPC Class Codes: H04L 69/169 Special adaptations of TCP, UDP or IP for interworking of IP based networks with other networks protocols for interworking, protocol conversion H04L69/08
• CPC Class Codes: H04M 15/51 for resellers, retailers or service providers
• CPC Class Codes: H04M 15/75 Account location specifications
• CPC Class Codes: H04M 15/765 Linked or grouped accounts, e.g. of users or devices
• CPC Class Codes: H04M 15/7655 shared by technologies
• CPC Class Codes: H04M 15/772 per service, e.g. prepay or post-pay
• CPC Class Codes: H04M 15/773 per technology, e.g. PSTN or wireless
• CPC Class Codes: H04M 2215/32 Involving wireless systems
• CPC Class Codes: H04M 2215/54 Resellers-retail or service providers billing, e.g. agreements with telephone service operator, activation, charging/recharging of accounts
• CPC Class Codes: H04M 2215/72 Account specifications
• CPC Class Codes: H04M 2215/724 Linked accounts
• CPC Class Codes: H04M 2215/725 Shared by technologies, e.g. one account for different access technologies
• CPC Class Codes: H04M 2215/7263 per service, e.g. prepay and post-pay
• CPC Class Codes: H04M 2215/7268 per technology, e.g. PSTN or wireless
• CPC Class Codes: H04W 36/0011 : for data sessions of end-to-end connection
• CPC Class Codes: H04W 36/14 : Reselecting a network or an air interface
• CPC Class Codes: H04W 4/24 : Accounting or billing
• CPC Class Codes: H04W 8/12 : between location registers or mobility servers
• CPC Class Codes: H04W 80/04 : Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A wireless data network includes a wireless packet switched data network for end users that divides mobility management into local, micro, macro and global connection handover categories and minimizes handoff updates according to the handover category. The network integrates MAC handoff messages with network handoff messages. The network separately directs registration functions to a registration server and direct routing functions to inter-working function units. The network provides an intermediate XTunnel channel between a wireless hub (also called access hub AH) and an inter-working function unit (IWF unit) in a foreign network, and it provides an IXTunnel channel between an inter-working function unit in a foreign network and an inter-working function unit in a home network. The network enhances the layer two tunneling protocol (L2TP) to support a mobile end system, and it performs network layer registration before the start of a PPP communication session.

Claims

1. A coupled data network comprising:

a foreign network that includes a base station, a wireless hub, and a foreign mobile switching center with a serving registration server, and a serving inter-working function;

a home network that includes a home mobile switching center with a home registration server and a home inter-working function; and

an end system subscribed to the home network and operating within the foreign network, the end system including an end registration agent to form a registration request, the registration request including an indication of a desired communications network having a desired communications server, the end system sending the registration request to the serving registration server, the serving registration server including a first module to process the registration request and to determine an optimum route between the desired communications server and one of the home inter-working function and the serving inter-working function, the serving registration server further including a second module to link the serving inter-working function to the desired communications server when the first module determines that the optimum route is between the serving inter-working function and the desired communications server.

2. The data network of claim 1, wherein the serving registration server further includes a third module to send to the home registration server the registration request with an appended indication that the service registration server has linked the serving inter-working function and the desired communications server.

3. The data network of claim 1, wherein:

the desired communications server is one communication server of a plurality of communications servers in the desired communications network; and

the first module includes a sub-module to determine the desired communications server from among the plurality of communications servers.

4. The data network of claim 1, wherein said home network and said foreign network share billing information for the end system when the end system is operating in the foreign network.

5. A coupled data network comprising:

a foreign network that includes a base station and a foreign mobile switching center with a serving registration server, the base station including an access hub with a serving inter-working function;

a home network that includes a home mobile switching center with a home registration server and a home inter-working function; and

an end system subscribed to the home network and operating within the foreign network, the end system including an end registration agent to form a registration request, the registration request including and indication of a desired communications network having a desired communications server, the end system sending the registration request to the serving registration server, the serving registration server including a first module to process the registration request and to determine an optimum route between the desired communications server and one of the home inter-working function and the serving inter-working function, the serving registration server further including a second module to send to the home registration server the registration request with a first appended indication that the serving registration server has determined that the optimum route is between the serving inter-working function and the desired communications server and a second appended indication that route optimization is preferred.

6. The data network of claim 5, wherein:

the desired communications server is one communication server of a plurality of communications servers in the desired communications network; and

the first module includes a sub-module to determine the select the desired communications server from among the plurality of communications servers.

7. The data network of claim 5, wherein the serving registration server includes a third module to establish a link between the serving inter-working function and the desired communications processor after sending the registration request and the first and second appended indications to the home registration server.

8. The data network of claim 7, wherein:

the home registration server includes a fourth module to send a registration reply to the serving registration server, the registration reply including an indication of that the link between the serving inter-working function and the desired communications server is approved; and

the home registration server further includes a fifth module to instruct the home inter-working function to transfer a link state to the serving inter-working function.

9. The data network of claim 5, wherein said home network and said foreign network share billing information for the end system when the end system is operating in the foreign network.

10. A method for optimizing routing in a coupled data network wherein the coupled data network comprises a foreign network that includes a base station and a foreign mobile switching center with a serving registration server, the base station including an access hub with a serving inter-working function, a home network that includes a home mobile switching center with a home registration server and a home inter-working function, and an end system subscribed to the home network and operating within the foreign network, the end system including an end registration agent to form a registration request, comprising the steps of:

generating a registration request at the end system, said registration request including an indication of a desired communications network having a desired communications server;

sending the registration request from the end system to the serving registration server;

processing the registration request in a first module in the serving registration server to determine an optimum route between the desired communications server and one of the home inter-working function and the serving inter-working function;

linking the serving inter-working function to the desired communications server when the first module determines that the optimum route is between the serving inter-working function and the desired communications server.

11. The method of claim 10, further comprising the step of:

sending to the home registration server the registration request with an appended indication that the service registration server has linked the serving inter-working function and the desired communications server.

12. The method of claim 10 wherein:

the desired communications server is one communication server of a plurality of communications servers in the desired communications network; and

the first module includes a sub-module to determine the desired communications server from among the plurality of communications servers.

13. The method of claim 10, wherein said home network and said foreign network share billing information for the end system when the end system is operating in the foreign network.

14. A method for optimizing routing in a coupled data network wherein the coupled data network comprises a foreign network that includes a base station and a foreign mobile switching center with a serving registration server, the base station including an access hub with a serving inter-working function, a home network that includes a home mobile switching center with a home registration server and a home inter-working function, and an end system subscribed to the home network and operating within the foreign network, the end system including an end registration agent to form a registration request, comprising the steps of:

generating a registration request at the end system, said registration request including an indication of a desired communications network having a desired communications server;

sending the registration request from the end system to the serving registration server;

determining whether the serving inter-working function or the home inter-working function is closer to the desired communications server;

instructing the serving inter-working function to establish a connection to the desired communications server when the serving inter-working function is closer to the desired communications server than the home inter-working function;

informing the home registration server that the end system is being served by the serving inter-working function and the desired communications server.