Study On The Clock Signal Of Basic Transmission Network

Transmission network is a basic carrier network that carries many application networks such as Digital Cell Network, IP network and Signaling Network 7 (SS7). Therefore, the high-quality operation of such application networks is based on the high-quality operation of the transmission network. The transmission network has many critical operation indexes that are closely related with clock synchronization such as error code, jitter and drift. For example, clock problems on a main transmission line will cause enormous adjustment of clock to the main transmission line, which will impose influence over system transmission quality of transmission network and thus further exert an influence on various networks that the transmission network carries. Therefore, maintenance personnel of telecommunication network shall value the reasonable application of synchronous timing signal and actively improve the existing clock synchronization to enhance the overall quality of transmission network. In addition, for other various equipments in communication network, such as"Digital Switching Equipment","Packet Switching Exchanger(X.25)"and"Signaling System 7 (SS7)", they all need to get precise synchronization information, which is the prerequisite for guaranteeing the communication quality and further ensuring the normal operation. The article deeply probes into the matter of transmission of the clock signal in the transmission network.The article compares and analyzes the actual transmission conditions of clock signal in several systems of transmission network, and finds out the differences and the existing problems. The article emphasizes the study of the clock transmission of SDH system that is widely used in current transmission network, probes into the theory of protection switch clock and its layout principle, and puts forward some new solutions through some examples. Meanwhile, aiming at facilitating the engineering maintenance, the article makes a comparison of the transmission performances of the clock under different conditions by using the network management system of the clock. The article also makes an analysis on the frequently-encountered faults of protection switch clock and gives a series of constructive advice on the maintenance of the clock of transmission network and some referrible basis.