Communications control for extending the period over which a terminal is able to have an open connection with a host accessible via a packet data network

• US 7,684,346 B2
• Filed: 12/29/2006
• Issued: 03/23/2010
• Est. Priority Date: 12/29/2006
• Status: Active Grant

• Current Assignee: WSOU Investments, LLC (WSOU Holdings, LLC)
• Original Assignee: Nokia Corporation
• Inventors: Valli, Jyrki
• Primary Examiner(s): Yao; Kwang B
• Assistant Examiner(s): Tran; Tung Q
• Application Number:
  US11/647,614
• Publication Number:
  US 20080159163A1
• Time in Patent Office: 1,180 Days
• Field of Search: 370241-253
• US Class Current: 370/252
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 61/2553 Binding renewal aspects, e.g. using keep-alive messages
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04W 76/25 Maintenance of established connections
• CPC Class Codes: H04W 80/06 Transport layer protocols, e.g. TCP [Transport Control Protocol] over wireless transmission control protocol/Internet protocol [TCP/IP] or user datagram protocol [UDP] H04L69/16

Abstract

A client and a host communicate in a packet data network including a plurality of routing nodes such as routers and firewalls. The host is configured to provide the client with a session and to detect the accessibility of the client by repeatedly sending keep-alive messages to the client. In order to reduce the traffic actually arriving at the client, at least some of the keep-alive message are adjusted such that their routing towards the client will be stopped before the client by storing in a Time-To-Live field specified in the Internet Protocol a value of maximum routing hops defined to correspond with the last routing node before the client on a route from the host to the client. The adaptation of the keep-alive message can also be configured to allow some keep-alive message to reach the client to occasionally test the communication path between the client and server.

Claims

1. A method comprising:

outputting in a packet data network a first data packet from a network party towards a terminal;

associating the first data packet with a time-to-live (TTL) adjusted to enable the first data packet to reach one or more intervening network entities but not to enable the first data packet to reach the terminal, in order to maintain traffic through the one or more intervening network entities to postpone expiry of a connection between the terminal and the network party in the one or more intervening network entities; and

determining the number of hops remaining on the route of the first data packet to the terminal and the time-to-live associated with the first data packet is adjusted so that the time-to-live is set to be smaller than the determined number of hops.

2. A method according to claim 1, wherein the associating of the first data packet with the time-to-live occurs at an adaptation element other than the network party.

3. A method according to claim 1, further comprising outputting an acknowledgement to the network party responsive to the first data packet.

4. A method according to claim 3, wherein the outputting of the acknowledgment emulates sending the acknowledgement from the terminal.

5. A method according to claim 1, wherein the time-to-live is set to the measured number of hops subtracted by a predetermined amount, wherein the first data packet will pass the intervening network elements which are configured to close connections after certain duration of idle time.

6. A method according to claim 1, wherein the measuring of the number of hops is based on the network party outputting a first data packet with a predetermined number of hops configured in time-to-live to the terminal, the terminal sending to the network party a second data packet that contains an indication of the time-to-live of the first data packet when the terminal received it, wherein the number of hops on the route of the first data packet from network party to the terminal corresponds to the difference between the predetermined number and the indicated time-to-live of the first data packet.

7. A method according to claim 1, further comprising:

monitoring at an adaptation element the data traffic originating from the terminal and traveling via the adaptation element;

determining continuously from the data traffic an updated number of hops between the terminal and the adaptation element; and

automatically adjusting the time-to-live of the first data packet according the updated number of hops.

8. A method according to claim 1, further comprising:

monitoring data traffic originating from the terminal and traveling towards the network party;

detecting a change in routing of the data traffic between the terminal and the network party; and

responsive to the detecting of the change in routing;

1) initiating a measurement procedure including transmitting a probing data packet to the terminal in order to determine a change in the number of hops between the terminal and the network part; and

2) automatically adjusting the time-to-live of the first data packet according the determined change.

9. A method according to claim 8, wherein the packet data network comprises an adaptation element configured to access data packets traveling between the network party and the terminal, configured to perform the monitoring, detecting, initiating and automatic adjusting.

10. A method according to claim 1, wherein the terminal detects an incoming first data packet and responsively sends an indication that the number of the hops between the network party and the terminal has changed.

11. A method according to claim 10, further comprising the terminal further sending an indication of an updated number of hops responsive to the detecting of an incoming first data packet.

12. A method according to claim 1, further comprising performing the steps of outputting the first data packet and associating the time-to-live repeatedly with a first interval.

13. A method according to claim 1, wherein the packet data network comprises an adaptation element configured to access data packets traveling between the network party and configured to measure the number of hops between the adaptation element and the terminal with a second interval.

14. A method according to claim 1, further comprising sending a keep-alive message from the terminal to the network party at a third interval in order to ensure that the network party is still accessible to the terminal.

15. A method according to claim 1, further comprising the terminal selectively acknowledging received keep-alive data packets according to a predetermined scheme.

16. A method according to claim 10, wherein the acknowledging of received keep-alive data packets by the terminal is dependent on meeting at least one of the following criteria:

having received a predetermined number of keep-alive data packets since previously acknowledging of a received keep-alive data packet, meeting a predetermined interval since previously acknowledging of a received keep-alive data packet, detecting a predetermined instruction from the network party, detecting a predetermined command associated with the most recently received keep-alive data packet, and detecting a predetermined command associated with the second most recently received keep-alive data packet.

17. An apparatus, comprising:

a processor;

memory including computer program code;

the memory and the computer program code configured to, with the processor, cause the apparatus at least to perform;

inputting a first data packet traveling in a packet data network from a network party towards a terminal, which packet data network comprises one or more intervening network entities on a route between the network party and the terminal;

associating the first data packet with a time-to-live adjusted to enable the first data packet to reach the one or more intervening network entities but not to enable the first data packet to reach the terminal, in order to maintain traffic through the one or more intervening network entities in order to postpone expiry of a connection between the terminal and the network party in the one or more intervening network entities; and

determining the number of hops remaining on the route of the first data packet to the terminal; and

adjusting the time-to-live associated with the first data packet so that the time-to-live is set to be smaller than the determined number of hops.

18. An apparatus according to claim 17, wherein the apparatus is integrated or functionally contained in the network party.

19. An apparatus according to claim 17, wherein the apparatus is configured to output an acknowledgement to the network party responsive to the first data packet.

20. An apparatus according to claim 17, wherein the outputting of the acknowledgment is configured to emulate sending the acknowledgement from the terminal.

21. An apparatus according to claim 17, further configured to set the time-to-live to the measured number of hops subtracted by a predetermined amount, wherein adapted to cause the first data packet will pass the intervening network elements which are configured to close connections after certain duration of idle time.

22. An apparatus according to claim 17, further configured to measure the number of hops by:

outputting a first data packet with a predetermined number of hops configured in time-to-live to the terminal;

receiving from the terminal a second data packet that contains an indication of the time-to-live of an first data packet when the terminal received it, wherein the number of hops on the route of the first data packet from network party to the terminal corresponds to the difference between the predetermined number and the indicated time-to-live of the first data packet.

23. An apparatus according to claim 17, further configured to:

monitor the data traffic originating from the terminal and traveling via the apparatus;

determine continuously from the data traffic an updated number of hops between the terminal and the apparatus; and

automatically adjust the time-to-live of the first data packet according the updated number of hops.

24. An apparatus according to claim 17, further configured to:

monitor data traffic originating from the terminal and traveling towards the network party;

detect a change in routing of the data traffic between the terminal and the network party; and

responsive to the detecting of the change in routing;

1) initiate a measurement procedure including transmitting a probing data packet to the terminal in order to determine a change in the number of hops between the terminal and the network part; and

2) automatically adjust the time-to-live of the first data packet according the determined change.

25. An apparatus according to claim 17, further configured to output the first data packet and associate the time-to-live repeatedly with a first interval.

26. An apparatus according to claim 17, further configured to access data packets traveling between the network party and configured to measure the number of hops between the apparatus and the terminal with a second interval.

27. A computer readable medium having stored therein a computer program comprising computer executable program code configured to control an intermediate network element, comprising:

computer executable program code configured to cause the intermediate network element to input a first data packet traveling in a packet data network from a network party towards a terminal, which packet data network comprises one or more intervening network entities on a route between the network party and the terminal;

computer executable program code configured to cause the intermediate network element to associate the first data packet with a time-to-live adjusted to enable the first data packet to reach the one or more intervening network entities but not to enable the first data packet to reach the terminal, in order to maintain traffic through the one or more intervening network entities in order to postpone expiry of a connection between the terminal and the network party in the one or more intervening network entities, and

computer executable program code configured to determine the number of hops remaining on the route of the first data packet to the terminal; and

to adjust the time-to-live associated with the first data packet so that the time-to-live is set to be smaller than the determined number of hops.

28. An apparatus, comprising:

means for inputting a first data packet traveling in a packet data network from a network party towards a terminal, which packet data network comprises one or more intervening network entities on a route between the network party and the terminal;

means for associating the first data packet with a time-to-live adjusted to enable the first data packet to reach the one or more intervening network entities but not to enable the first data packet to reach the terminal, in order to maintain traffic through the one or more intervening network entities in order to postpone expiry of a connection between the terminal and the network party in the one or more intervening network entities, wherein the apparatus is configured to determine the number of hops remaining on the route of the first data packet to the terminal; and

to adjust the time-to-live associated with the first data packet so that the time-to-live is set to be smaller than the determined number of hops.