UPPER TRAFFIC CONTROL METHOD IN AN ETHERNET PASSIVE OPTICAL NETWORK, SPECIALLY CORRELATED TO RESOLVING A PENALTY PHENOMENON OCCURRING WHEN DATA IS UPLINKED BY PRIORITY

摘要

PURPOSE: An upper traffic control method in an EPON(Ethernet Passive Optical Network) is provided to compare low watermarks set in each buffer with a quantity of data frames, and to transmit the data frames even though the data frames have lower priorities if the data frames are more than the low watermarks, thereby guaranteeing the priorities of the data frames while effectively using buffer resources. CONSTITUTION: An FIFO scheduler checks whether data frames exist in a buffer(S100). If so, the scheduler sends the data frames(S120), and decides whether data frames exist in the second buffer at less than low watermarks set for guaranteeing minimum traffic of transmission frames(S140). If not, the scheduler decides whether the data frames existing in the first buffer are less than the low watermarks(S160). If so, the scheduler transmits the data frames existing in the second buffer(S180). If data frames existing in the third buffer are more than the low watermarks(S200), the scheduler decides whether the data frames of the first buffer are less than the low watermarks(S220). If so, the scheduler transmits the data frames existing in the third buffer(S240).