Patent ID: 8451836
Filing Date: 2013-05-28
Classification: H04L,H04Q

Abstract:
1. A method for transmitting a constant rate data stream in a Gigabit-Passive Optical Network (GPON), comprising: Receiving, in a first network device, a constant rate data stream; calculating an input rate of the constant rate data stream or a rate difference between the input rate and a standard rate of the constant rate data stream in each cycle of a reference clock; encapsulating the constant rate data stream into a GPON Encapsulation Method (GEM) frame by using a bit as a minimum encapsulation unit, wherein the GEM frame carries rate information of the input rate or the rate difference, and a length range of a valid payload is fixed; and encapsulating the GEM frame into a GPON Transmission Convergence Layer (GTC) frame, and sending, by the first network device, the GTC frame to a second network device through the GPON network, wherein the second network device is an Optical Network Unit (ONU) when the first network device is an Optical Line Terminal (OLT), and the second network device is an OLT when the first network device is an ONU; wherein before receiving the constant rate data stream, the method further comprises: generating two physical clocks, wherein one physical clock is used as the reference clock, and the other physical clock is used as a line clock of an optical carrier for transmitting the GTC frame; wherein encapsulating the constant rate data stream into the GEM frame by using the bit as the minimum encapsulation unit further comprises: calculating a payload length of the GEM frame encapsulating the constant rate data stream, according to the standard rate of the constant rate data stream and the cycle of the reference clock.