Research And Design Of The Fusion Core Network

At early days of TD-LTE network construction, due to the limitation of wireless coverage, poor LTE wireless signal coverage area or no coverage area exists. The operator allows users to switch from 4G network to the 2G/3G wireless signal network in order to use service. Since the access net element and access method of 4G and 2G/3G are different, part of core network, whose controlling function is performed by different formatted networks, is not capable of meeting requirements of current status. Under the trend of mobile core network gradually evolving into IP network, the convergence of different formatted core network is the problem that must be solved. There is technical problem for convergence of different formatted core network: the interoperation of different formatted core network exists necessarily which makes low success rate of network switching and long delaying for location update; to establish independent core network will make the low utilization rate of equipment and high maintenance workload.Based on the above problems, this paper studies different formatted network of 2G/3G/4G for their networking schema and the corresponding function for their net elements in detail, combines the current situation of China Mobile, analyzes the networking schema of core network convergence of China Mobile. Technical analysis of technical schema for convergence of core network: to make the wireless access network of same or adjacent coverage zone be accessed with same MSC and SGSN; to accomplish the gradual transition of current service from circuit domain to packet domain to reduce the operations, such as the cell reselection across systems, location updating and switching; and to improve user perception. After adjustment and convergence, local network traffic goes to the circuit dredging via MSC without the transferring of GMSC, alternative routing is reduced and utilization of user resources is decreased. There is no need for user number partition after convergence HLR's construction which helps to unified storage of user data and centralized management.According to the current status of user scale and business requirement in Gansu Mobile and based on the requirement scale analysis of users and business development from different perspectives, this paper proposes, plans and deploys the network construction schema of Gansu Mobile core network convergence. The core network convergence schema of Gansu Mobile takes two steps gradually for implementation from two aspects: circuit domain and packet domain. In the respect of circuit domain, the paper analyzes the end office which is responsible for different domain and related net elements of gateway, at the same time it proposes the corresponding convergence reform schema and the capacity expansion requirement of current net elements for gateway, and completes the HSS convergence reform of signaling network's distribution structure HLR.In terms of packet domain,the paper analyzes the current status of packet domain's net elements which are in charge of different fields in Province,suggests corresponding convergence reform plan on the basis of this,and proposes corresponding capacity expansion requirement of existing net elements,e.g.SGSN,GGSN,CG,PCRF and DNS.Through the research, deployment, plan and design of Gansu Mobile's core network convergence schema, the related engineering has been completed and put into operation successfully. The late statistical indicators completely satisfy the requirements of core network convergence. The technical schema of core network convergence in Gansu Mobile concludes: the networking method of early deployment of core network convergence makes signal interaction and media route be clearer. The data service is born with EPC core net elements; the voice service is solved in CSFB and dual standby way. During the whole process of signal interaction, the optimized remote process controls the switch time effectively and the clear network structure decreases the failure points.