Method for Enhancing the Reliability of the Continuity of the Communications Operated from a 4G Mobile Terminal Linked to an IP Interconnection Network

• US 20130083716A1
• Filed: 09/26/2012
• Published: 04/04/2013
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Thales SA
• Original Assignee: Thales SA
• Inventors: MATHIEU, Christophe, MARTINEZ, Natael
• Granted Patent: US 8,923,185 B2
• Time in Patent Office: Days
• US Class Current: 370/312
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 8/085 involving hierarchical organized mobility servers, e.g. hierarchical mobile IP [HMIP]
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A method for guaranteeing with a high level of reliability the continuity of the communications operated from a fourth-generation mobile terminal linked to a level-3 interconnection network, in the terminology defined by the OSI, uses gateways to maintain location information about the mobile terminals. The method applies notably to the mobility of mobile terminals in a context which is highly intolerant to faults, for example for networks used by military forces, public bodies, or civil agents such as the police, fire brigade or civil security. In particular, it may be implemented in networks liable to experience breaks in communication links in the interconnection network.

Claims

1. A method for guaranteeing the continuity of the communications operated from a fourth-generation mobile terminal connected to a radio network provided with several base stations with which said terminal is able to communicate, a base station being affiliated to a controller from among several controllers linking said radio network to an interconnection network comprising routers operating at the level of the IP layer, at least one controller being connected to at least one gateway configured to encapsulate in IP packets all the IP packets arising from the radio network before broadcasting them over the interconnection network, the method comprising at least the following steps:

when a mobile terminal connects to a base station affiliated to a controller to which the mobile terminal was not affiliated hitherto, said controller transmits to a gateway a level-2 message comprising at least the IP address of the mobile terminal,

said gateway creates, at the level of the IP layer, a message comprising the IP address of said mobile terminal and the IP address of said gateway in the interconnection network,

said IP message is broadcast by said gateway to destination gateways associated with the other controllers, each of said destination gateways storing a correspondence between the IP address of the mobile terminal and the IP address of the sending gateway associated with the controller to which the mobile terminal is affiliated.

2. The method according to claim 1, the gateways being accessible through at least two different IP addresses, a first IP address being known to the nodes of the radio network, a second IP address being known to the nodes of the interconnection network, in which all the IP packets arising from a controller are systematically transmitted to the gateway with which it is associated, said gateway encapsulating said IP packets in other IP packets whose destination IP address is the second address of a destination gateway.

3. The method according to claim 1, wherein each controller is connected to a gateway specific to this controller.

4. The method according to claim 3, in which each gateway is connected to the controller at which it is located by way of at least one IP router included in the interconnection network, said router being configured to systematically guide all the IP packets or level-2 messages to said gateway, prior to their encapsulation and broadcasting in the interconnection network.

5. The method according to claim 2, in which, after the encapsulation step, all the packets arising from a first gateway connected to a first controller travel via the interconnection network and are then transmitted to a second gateway connected to a second controller, this second gateway removing the IP capsule added to the IP packets by the first gateway before transmitting said IP packets to the second controller.

6. The method according to claim 2, in which the first IP address known to the nodes of the radio network is the same for all the gateways.

7. The method according to claim 1, in which, when a router sends an ARP request to the interconnection network, the first router of the interconnection network receiving said request transmits it to a gateway, said gateway transmitting a response to said router, the response comprising the level-2 address of said gateway.

8. A system for guaranteeing the continuity of the communications operated from a fourth-generation mobile terminal connected to a radio network provided with several base stations with which said terminal is able to communicate, said radio network being linked by controllers to an interconnection network comprising routers operating at the level of the IP layer, wherein each controller is connected to at least one gateway configured to encapsulate in IP packets all the IP packets arising from the radio network before broadcasting them over the interconnection network.

9. The system according to claim 8, in which at least one gateway is connected via a data bus to the controller with which it is associated.

10. The system according to claim 8, in which at least one gateway is connected by way of at least one router to the controller with which it is associated.