Patent ID: 7949878
Filing Date: 2011-05-24
Classification: H04L

Abstract:
1. A method for providing a time stamp by using a tamper-proof time signal via a telecommunications network comprising the steps of: receiving, at a central system, a request from one of a plurality of network users for a time signal, the central system comprising a plurality of clock systems, wherein each of the plurality of clock systems of the central system is uniquely assigned to one of the plurality of network users, the request including an identifier uniquely assigned to the network user; identifying, by the central system based on the received identifier uniquely assigned to the network user, one of the plurality of clock systems thereof uniquely assigned to the network user; encrypting said time signal by the central system with at least one key obtained from the clock system uniquely assigned to the network user; transmitting the encrypted time signal to the one of the plurality of network user assigned to the identified clock system via the telecommunications network; synchronously creating the at least one key by the clock system of the central system uniquely assigned to the network user and a clock system of the network user corresponding to the uniquely assigned clock system of the central system; and determining, by the central system, a location of the network user based on the identifier uniquely assigned to the network user.