Research On Safety Problems Of Yunnan MCC Core Network And Relative Solutions

Mobile Communication Network is the infrastructure for providing civil personal communication services. Comparing to access network, which is characteristic of diverse distribution, core network is of convergence distribution and end-to-end connection. Therefore, once any occurrence of safety problem in core network would lead to chance failure, disaster, catastrophe, covering a large range of communication service area, even the whole network. In order to assure the validity of core network, it is necessary to take measures against safety problems.The author has been specializing in core network planning and designing for many years, and quite familiar with Yunnan MCC network hierarchy. This paper closely inspects the core network of Yunnan MCC, resulting in a detailed analysis of the current problems:(1)Risks rise up from network elements convergence.With the trends of convergence, core network elements have been centralized than ever. At present, two site-locations host most of Yunnan MCC core network elements, which gives rise to more risks of destructive malfunction.(2)For single network element, there are still some problems to be solved. HLR: redundancy system based on BOSS is unable to backup dynamic data, and does not function yet; MSS: steps needed to improve the bilateral backup performance among those network nodes; SCP & SGSN: far beyond construction of redundancy system; traditional 2G network elements, such as BSC, MSC, even MGW, can but make use of redundant circuits or emergency cut-over to guard normal communication connection because lack of technical solution.(3)It is necessary to strengthen bi-plane network.Typically, bi-plane network refers to STP, TMSC, GMSC, etc. In case of one single plane failure, the other one can not take over all the traffic due to capacity limit.Taking one consideration with another, this paper brings forward various solutions relative to each problem.Firstly, the threat of the central buildings' failure has a great impact on a couple of network elements, or even several entire networks. Hence, it is most important to construct another centre for housing core network elements.Secondly, as the key network element, subscriber register database (HLR) plays a key role in mobile communication service. While newly developed HLR of huge capacity being put in operation, the rank of its safety grows accordingly. It requires that operator constructs a backup system for HLRs to avoid suffering from service failure.Thirdly, as for MSS, SGSN, SCP/VC, these network elements not only perform control function, but also store service logics. Thus, through "N+1" backup or "double residence" solution, HLRs can improve their robustness.Fourthly, bi-plane framework ensures the network against unexpected calamity by building two equal networks. The key solution to bi-plane framework is to expand each network's capacity.According the above solutions, concrete schemes are laid out as follows respectively: new centre for core network elements; HLR redundancy system; MSS backup system; SGSN backup system; SCP/VC backup system; bi-plane network.In conclusion, correspondent solution and scheme should be proposed, which must concentrate on technical factor and take financial devotion into account as well, to meet the needs of various safety problems of core network.