METHOD FOR COMPENSATING ROUND TRIP DELAY IN TRANSMISSION OF ETHERNET FRAMES OVER A PASSIVE OPTICAL NETWORK AND PASSIVE OPTICAL NETWORK SYSTEM THEREFOR

摘要

In the passive optical network termination unit with a tree structure consisting of optical network unit to sunlight, the rays Termination device in this way to compensate for the round-trip delay time to meet the clock synchronization between the optical network unit, the first process and to measure the round trip time for the i-th optical network unit in the registration step, the end device to the beam is the first time in his clock, recording the sum of the round trip time (i) the first time and the measurement in the time stamp field, and recording the desired received time slot gate to receive the slots to be allocated to the Start field Part B and sends the message to the optical network unit, the optical network device receives the message, the gate, fit its local clock to the time count on it to the time stamp of the received message, and a gate, their local based on the clock, in time slot written in the start field of the received message gate, reported to be characterized by the time desired received constituted by the third process of sending a message.