Abstract: In order to solve the problems of instantaneity, low retardance and reliability, which related to the train Ethernet correspondence system, this thesis studies the present development of railway transmission network and
analyzes the main factors influencing Ethernet according to the standard IEC 61375-2-5 and IEC 61375-3-4. Basing on the present research, this thesis presents a scheduling algorithm based on the high instantaneity and low retardance of industry Ethernet, which can also be used for train correspondence system. The simulation research shows that the performance of this optimization scheduling algorithm is 10 times better than the traditional queue data transmission algorithm.

Key words: Ethernet, reliability, scheduling algorithm, low retardance, instantaneity