Application of MSTP technology in multimedia and 3G network

Customer network node of the line voice (such as private network voice trunk), 2M digital circuits, broadband IP internet access, DDN and other services integrated access.

3.1.5 MSTP applied to future 3G network

The mainstream of 3G mobile communication includes WCDMA, CDMA2000 and TS-CDMA, among which WCDMA has the most kinds of transmission interfaces, including STM interface, ATM interface, IMA interface and Ethernet (Fe/ge) interface. 3G network should give full consideration to interface support capability, voice and data service support capabilities, transmission efficiency and bandwidth utilization, as well as the security and reliability of networks and other factors. From the 3G development, WCDMA commercial version has R99 and R4, the network uses ATM architecture, and there is the possibility of the evolution of IP mode to the whole network. MSTP inherits the traditional SDH support for TDM service, and has the support of dynamic ATM and IP service transmission, so the MSTP platform is an ideal way of transmission network.

In 3G networks, there are two types of interfaces between the more dispersed Node-b and the RNC: IMA 2M and atm155m. MSTP can improve the transmission efficiency of the dynamic service and make the Ring network protection, the large local network can connect the node-b to the RNC through the convergence layer; for small local networks, the node-b of the access layer can be directly connected to the RNC of the core layer, and the local network can also be based on base station (node-b The actual configuration is mixed application. (Computer science)

3.2 Protection mode

(1) for the Ethernet service transmission and the two-layer switch can directly use SDH to provide the reusable segment protection, subnet connection protection.

(2) The layered protection method can be used for the Ethernet ring network. The physical layer uses the SDH Multiplex segment protection to provide the Ethernet service protection; The MAC layer uses the Spanning tree protocol to provide the Ethernet service protection. When the MAC layer switching and physical layer switching start simultaneously, the delay MAC layer switching time can be used to support the interlayer switching.

(3) In practical application, the user-level protection mechanism can be implemented, and the important data User Service can adopt the layered protection method, and the general Data User Service should be protected with MAC layer spanning tree protocol.

3.3 Several problems needing attention in applying MSTP technology network

3.3.1 the proportion of different technology applications

MSTP technology is a breakthrough in transmission technology. It can be seen that there are breakthroughs in the different areas of telecommunications technology between the various technologies. For example, in the development of multimedia technology, Gigabit Ethernet technology breakthrough to promote the rapid development of broadband IP network, to a certain extent, so that the application of ATM technology to reduce the situation. Although there is a convergence of technologies in different areas, the diversity of applications determines the impossibility of using a technology to solve all problems. As previously mentioned protection methods, based on Ethernet STP switching and SDH technology based switching also have different applications.

From the test situation, MSTP technology provides the link bandwidth below 2.5G, for broadband IP metropolitan Area Network, the link above the convergence layer is usually 2G or even 10G, which makes the MSTP in the Broadband network access layer below the application is more powerful. The test found that the MSTP system has very limited ATM capabilities and does not support SVC and dynamic switching.

Therefore, according to different business needs to adopt different technical combination, for telecommunications network is necessary, but also more appropriate.

3.3.2 of interoperability between different manufacturers

As the GFP encapsulation, the service interface rate and SDH actual line rate is different, they are no longer the VC12, VC3, VC4 multiples of the relationship, at the same time, the various manufacturers Ge/fe VC package level situation is not the same. The specific application needs to configure the VC particle encapsulation according to the business situation to improve the utilization of the bandwidth resources.

Operators in the organization of some tests found that interoperability between different manufacturers still have problems, especially Ethernet interoperability, some can not exchange, and some need to switch off FCS to exchange.

In the QoS implementation mechanism, the understanding between different manufacturers is also different, which makes the telecom operators only adopt one product to achieve QoS, but this is actually impossible.

The problem of 3.3.3 network management

From the current development of the telecommunications market, operators are increasingly stressed through a comprehensive network management to achieve the same professional equipment of different manufacturers of the unified administration. However, at present, MSTP manufacturers can still only manage their own equipment, therefore, how to achieve the whole process of management still need to be further resolved.

4 Summary

MSTP as a breakthrough in transmission technology, the author believes that there is no need to discuss the use of the problem, because telecommunications in different areas of technology convergence is a trend, no technology can solve all areas of the problem is also a reality. Therefore, to MSTP, it is necessary to focus on the appropriate application of the problem, in the application of the current MSTP technology to solve the deficiencies.

Wei Fang, female, assistant engineer June 1996 graduated from the Nanjing University of Posts and telecommunications professional mobile communications. Now Jiangsu Mobile Communication Co., Ltd. is working. has been engaged in the construction and maintenance of mobile communication equipment, at present, mainly responsible for the network management and optimization of mobile GPRS core network in Jiangsu province.