Patent ID: 7804838

Claim:
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.