Time synchronizing device and process and associated products

• US 7,804,838 B2
• Filed: 01/03/2005
• Issued: 09/28/2010
• Est. Priority Date: 01/09/2004
• Status: Expired due to Fees

• Current Assignee: InterDigital Patent Holdings, Inc. (InterDigital, Inc.)
• Original Assignee: Thomson Licensing (Vantiva SA)
• Inventors: Dumet, Sylvain, Van De Poel, Dirk
• Primary Examiner(s): Kumar; Pankaj
• Assistant Examiner(s): SMITH, MARCUS
• Application Number:
  US10/585,534
• Publication Number:
  US 20090201936A1
• Time in Patent Office: 2,094 Days
• Field of Search: None
• US Class Current: 370/401
• CPC Class Codes: H04J 3/0641 Change of the master or reference, e.g. take-over or failure of the master
• CPC Class Codes: H04L 67/02 based on web technology, e.g. hypertext transfer protocol [HTTP]
• CPC Class Codes: H04L 67/56 Provisioning of proxy services store-and-forward switching systems in data switching networks H04L12/54
• CPC Class Codes: H04L 67/563 Data redirection of data network streams
• CPC Class Codes: H04L 67/564 Enhancement of application control based on intercepted application data
• CPC Class Codes: H04L 69/28 Timers or timing mechanisms used in protocols
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

The present invention concerns a time synchronizing device and process, and a local gateway comprising that device. The time synchronizing device synchronizes a router arranged between two communication networks. It comprises intercepting means of a message coming from an apparatus of a source network for that message, having a specific time clock, and directed to a target network for that message, preparing means of a time request able to be executed in that apparatus so as to cause synchronizing data based on that specific clock to be obtained from that apparatus and to be transmitted back to the synchronizing device, sending means of the time request to the apparatus, forwarding means of the intercepted message to the target network after the preparing means have prepared the time request, receiving means of the synchronizing data, and exploiting means of those data to synchronize a local time clock used by the router with respect to that specific time clock .Application to home networks.

Claims

1. A time synchronizing device for synchronizing a router arranged between a first and a second communication network, said synchronizing device comprising:

receiving means for receiving first synchronizing data based on a reference time clock from said first communication network, and

exploiting means for exploiting said first synchronizing data (SYNC) to synchronize a local time clock used by said router with respect to said reference time clock,

wherein said time synchronizing device comprises;

intercepting means for intercepting a message (MSG) coming from an apparatus of said second communication network and directed to said first communication network, said apparatus of said second communication network having a specific time clock,

preparing means for preparing a time request intended for said apparatus of said second communication network periodically or responsive to a state of said local time clock of said router, said time request for execution in said apparatus of said second communication network to cause second synchronizing data based on said specific time clock to be obtained from said apparatus of said second communication network and to be transmitted back to said time synchronizing device and to cause caching of the message (MSG),

sending means for sending said time request to said apparatus of said second communication network, and

forwarding means for forwarding said cached, intercepted message (MSG) to said first communication network after the preparing means has prepared said time request,

said receiving means for further receiving said second synchronizing data from said apparatus of said second communication network and said exploiting means for further exploiting said second synchronizing data to synchronize said local time clock with respect to said specific time clock, said receiving means, exploiting means, intercepting means, preparing means, sending means and forwarding means forming an operational set.

2. The time synchronizing device according to claim 1, wherein said intercepting means intercepts said message and said receiving means receives and extracts said second synchronizing data in compliance with HTTP protocol.

3. The time synchronizing device according to claim 1, wherein said preparing means prepares the time request in the form of executable scripts based on Java.

4. The time synchronizing device according to claim 1, wherein said forwarding means forwards said cached, intercepted message (MSG) to said first communication network only after the exploiting means exploits said second synchronizing data obtained from said apparatus of said second communication network by means of said time request.

5. The time synchronizing device according to claim 1, wherein said preparing means prepares said time request for getting one of synchronizing local data time zone and daylight saving time information.

6. The time synchronizing device according to claim 1, wherein said time synchronizing device comprises updating means for periodically updating said second synchronizing data based on said specific time clock to synchronize said local time clock by periodically activating said operational set, said updating means using as said intercepted message for each of said updating periods, a first message received from said second communication network during said updating period.

7. The time synchronizing device according to claim 1, wherein said time synchronizing device comprises safety means for activating said operational set for two successive messages from respectively two different apparatus of said second communication network, to compare said second synchronizing data respectively obtained for said successive messages, to check consistency of said synchronizing data and to trigger a warning mechanism in case of inconsistency.

11. The time synchronizing device according to claim 1 wherein said cached, intercepted message (MSG) comprises an HTTP information request message directed to a data server of the first communication network.

8. A local gateway intended to be arranged between a LAN and a WAN to enable communication in both directions between the LAN and the WAN, said local gateway comprising:

a LAN interface for communication with the LAN,

a WAN interface for communication with the WAN,

a local gateway time clock, and

synchronizing means for synchronizing said local gateway time clock with respect to a global reference time clock by means of first synchronizing data received by said local gateway,

wherein said synchronizing means comprises a time synchronizing device for synchronizing said local gateway, the time synchronizing device comprising;

intercepting means for intercepting a message (MSG) from an apparatus of the LAN and directed to the WAN, said LAN apparatus having a specific time clock,

preparing means for preparing a time request for said LAN apparatus periodically or responsive to a state of said local gateway time clock, said time request for execution in said LAN apparatus to cause second synchronizing data based on a specific time clock of said LAN apparatus to be obtained from said LAN apparatus and transmitted back to the time synchronizing device and to cause caching of said message (MSG),

sending means for sending said time request to said LAN apparatus, and

forwarding means for forwarding said cached, intercepted message (MSG) to said WAN after the preparing means has prepared said time request,

said synchronizing means comprising receiving means for receiving said second synchronizing data from said LAN apparatus and exploiting means for exploiting said second synchronizing data to synchronize said local gateway time clock with respect to said specific time clock.

9. The local gateway according to claim 8, wherein said synchronizing means synchronizes said local gateway time clock with respect to said global reference time clock available from a timeserver of the WAN.

10. A method for time synchronizing a router arranged between first and second communication networks, said method comprising:

receiving first synchronizing data based on a reference time clock from said

first communication network, and

exploiting said first synchronizing data to synchronize a local time clock used by said router with respect to said reference time clock,

wherein said time synchronizing method further comprises;

intercepting at least one message coming from an apparatus of said second communication network and directed to the first communication network, said apparatus of said second communication network having a specific time clock,

preparing a time request for said apparatus of said second communication network periodically or responsive to a state of said local time clock, said time request to be executed in said apparatus to cause second synchronizing data based on said specific time clock to be obtained back from said apparatus and caching of said intercepted message,

sending said time request to said apparatus, and

forwarding said cached, intercepted message to said first communication network after said time request has been prepared,

receiving said second synchronizing data from said apparatus and exploiting said second synchronizing data to synchronize said local time clock with respect to said specific time clock.

12. A non-transitory storing space with an executable program stored thereon, wherein the program instructs a computer in a router for time synchronizing between first and second communication networks to perform the following steps:

receiving first synchronizing data based on a reference time clock from said first communication network, and

exploiting said first synchronizing data to synchronize a local time clock used by said router with respect to said reference time clock,

wherein said time synchronizing method further comprises;

intercepting a message coming from an apparatus of said second communication network and directed to the first communication network, said apparatus of said second communication network having a specific time clock,

preparing a time request for said apparatus of said second communication network periodically or responsive to a state of said local time clock, said time request to be executed in said apparatus to cause second synchronizing data based on said specific time clock to be obtained back from said apparatus and caching of said intercepted message,

sending said time request to said apparatus, and

forwarding said cached, intercepted message to said first communication network after said time request has been prepared,

receiving said second synchronizing data from said apparatus and

exploiting said second synchronizing data to synchronize said local time clock with respect to said specific time clock.