MAINTAINING AN IP CONNECTION IN A MOBILE NETWORK

• US 20130003634A1
• Filed: 09/13/2012
• Published: 01/03/2013
• Est. Priority Date: 06/21/2005
• Status: Active Grant

• Current Assignee: Seven Networks LLC (SoftBank Group Corp.)
• Original Assignee: Seven Networks International Oy (SoftBank Group Corp.)
• Inventors: Backholm, Ari, Salorinne, Seppo, Ahonen, Jukka, Daavittila, Mikko, Everitt, Andrew, Vuornos, Lauri
• Granted Patent: US 8,761,756 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04L 43/0811 by checking connectivity
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04W 76/25 Maintenance of established connections
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A method for IP [=Internet Protocol] communication between a mobile terminal and its correspondent node in a mobile radio network. The method comprises establishing (202) an IP connection between the mobile terminal and its correspondent node. After detecting a period of inactivity in the IP connection, (204) keep-alive messages are sent via the IP connection at predetermined intervals, which are varied. The method comprises monitoring (206) the lengths of several periods of inactivity at which the mobile radio network disconnects the IP connection. Based on the monitored lengths of periods of inactivity, a maximum interval (T_INT) between keep-alive messages is determined (208) such that the maximum interval meets a predetermined criterion of statistical confidence, and the interval between keep-alive messages is set (210) to the maximum interval (T_INT).

Claims

1. A method of maintaining a connection between a mobile terminal and a network element in a network, the method, comprising:

altering a time interval between keep alive messages exchanged between the mobile terminal and the network element;

monitoring the Internet Protocol connection to determine if disconnection of the connection occurs as a result of the altering of the time interval between the keep alive messages;

determining a value for the time interval, the value being determined such that the connection with the network element is not disconnected and further determined based on an associated cost to send the keep-alive messages;

wherein, the cost to send the keep-alive messages includes battery life of the mobile terminal;

wherein, the time intervals are further determined statistically based on the disconnection of the connection.

2. The method of claim 1, further comprising re-establishing the connection between the mobile terminal and the network element when the connection is disconnected.

3. The method of claim 1, further comprising, exchanging the keep alive messages by sending the keep alive messages from the mobile device.

4. The method of claim 1, further comprising, exchanging the keep alive messages by sending the keep alive messages from the network element.

5. The method of claim 1, wherein, the value satisfies a statistical confidence;

wherein the statistical confidence is a variance.

6. The method of claim 5, wherein the statistical confidence is based on a safety margin, and further, wherein the safety margin is based on one or more of:

an amount of time subtracted from the value of the time interval;

a percentage of the value of the time interval.

7. The method of claim 5, wherein the statistical confidence is based on a cumulative probability function for the disconnection of the connection as a function of the time interval.

8. The method of claim 5, wherein altering the time interval comprises altering the time interval in both a predetermined and a variable manner.

9. The method of claim 1, further comprising storing the value for the time interval with an identifier of the network.

10. The method of claim 9, wherein the value for the time interval and the identified of the network are stored in the mobile device.

11. A server operative to maintain a connection with a mobile terminal in a mobile network, the server, comprising:

a processor programmed to execute a set of instructions;

memory coupled to the processor; and

the set of instructions stored in the memory, wherein the set of instructions are executed by the processor, the server maintains the connection between the mobile terminal and the server by;

altering a time interval between the keep alive messages exchanged between the mobile terminal and the network element;

monitoring the connection to determine if disconnection of the connection occurs as a result of the altering of the time interval between the keep alive messages;

determining a value for the time interval, the value being determined such that the connection with the network element is not disconnected and further based on battery life of the mobile terminal and a battery consumption involved in re-establishing the connection.

12. The server of claim 11, wherein, the value satisfies a criterion of statistical confidence.

13. The server of claim 12, wherein the criterion of statistical confidence is based on a safety margin, and further, wherein the safety margin is based on one or more of:

an amount of time subtracted from the maximum value of the time interval;

a percentage of the maximum value of the time interval;

or

a cost associated with sending the keep alive messages.

14. The server of claim 11, wherein the value for the time interval is determined based on a cumulative probability function for the disconnection of the connection as a function of the time interval.

15. The server of claim 11, wherein altering the time interval comprises altering the time interval in one or more of a predetermined and a variable manner.

16. A system for maintaining a connection of a mobile terminal in a network, comprising:

means for, dynamically adjusting time intervals between keep-alive messages sent by the mobile terminal;

means for, optimizing the time intervals between the keep alive messages based on a cost to send the keep-alive messages in the network and based on whether the keep-alive messages are sent with adequate frequency to maintain the connection;

wherein, the cost to send the keep-alive messages includes battery life of the mobile terminal.

17. The system of claim 16, wherein, the time intervals are adjusted according to statistical characteristics of the communication history across the connection.

18. The system of claim 16, wherein, the cost further includes the cost to re-establish the connection in the event of disconnection.

19. The system of claim 16, wherein, the cost further includes battery consumption involved in re-establishing the connection.

20. A method of maintaining a connection between a mobile terminal and a network node over a network, comprising:

dynamically adjusting time intervals between keep-alive messages sent across the connection between the mobile terminal and the network node;

optimizing the time intervals between the keep alive messages based on battery life of the mobile terminal and further based on whether the keep-alive messages are sent with adequate frequency to maintain the connection.