The Application Of Softswitch In 3G Network

Over the years, Carriers in China carried out a large-scale mobile communication network construction, size of network reached world leading level, the number of users continues to grow. After 3G licenses released, the construction of 3G network is the most important business to Carriers. How to construct the network by the most economical and most effective way ; How to build the most secure, most stable network; how to make the network transferred smoothly is the key point focused by the Carriers. Afer the 3G license releasing, the research of 3G and the softswitch sthetched out from the Lab. So the network planning is the most important to make the network secure.This article describes the function of soft switching, interface etc.; explained 3G technical standards, proposed by China Unicom's 2G, 3G network planning and coordinated development and the business strategy..Discussed the soft-switching in the WCDMA networking aspects of application. From the network deployment, the ability of evolution to IMS, the existing conditions etc. Discussed the choice of 3G core network softswitch version; put forward a variety of soft-switching networking program.From china operators in the present development , the cost-effectiveness, network stability, the soft-switching equipment, and the Networking Method of carrying capacity, we get three kinds of network disaster recovery programs.Also analyze and compare these three backup programs.Take a provincial capital city of pairs of ownership and "N +1" backup program as a example, which designed into a MSC POOL networking mode.Through the comparison of the network's operation which use MSC in POOL, we can see that the MSC in POOL of the networking mode can balance the networks's traffic, CP load, the number of users , also the switch nember between Office and location is significantly reduced , the security of network and system capacity are greatly enhanced.1. Soft-Switch TechnologySoft-switching technology solves the unified platform that offers more application of the business. Softswitch is the basic meaning of the separation of control and bearer. In the soft switch core network, the major new interface is: Mc, Nc, Nb.2. 3G Technology3G wireless network speeds in different circumstances: In the static, slow moving and fast-moving situations, the speed changes from, 2Mbps, 384kbps to 144kbps or more.3. Softswitch Networking Method discussed in the WCDMA networkWCDMA due to the popularity of the highest degree of GSM, as well as its widely supported; CDMA2000 can be smoothly transits from 2 G/2.5 G is also a biggest bright spot; TD-SCDMA as China's own intellectual property rights standards, its strengths are concentrated in air interface connection. This article only WCDMA as an example to illustrate this.3.1 Core Network version of the selectionCore network mainly consider from the following aspects for its version: network deployment perspective, the future evolution to IMS, the existing conditions. WCDMA core network construction at this stage is recommending R4 softswitch architecture, R4 MSC is seperates from MSC to MSC Server and MGW, MSC Server controls the completion of signaling, MGW offers traffic forwarding.3.2 Select Networking Method SoftswitchFor China, the Unicom companies operate both WCDMA and GSM networks. in the first stage, use the existing 2G network, in order to save investment, 3G core network element set can have three kinds of programs: program 1: 2G/3G set up independently MSC Server, set up independently MGW; Program 2: 2G, 3G shared MSC Server, set up independently MGW; program 3: 2G/3G shares MSC Server and MGW. Considrering comprehensive factors, we choose the program 2: 2G/3G sharing MSC Server, but differs from the building of their respective MGW.4. Softswitch Network Disaster Recovery Networking Program4.1 MSC Server Disaster Recovery Program to discussThere are 3 ways commonly used in disaster recovery programs.the program I "1 +1" dual ownership of the backup program; Program II "N +1" The disaster recovery programs; program III MSC in POOL solution. Compared through the three kinds of disaster recovery program, we see that the results of selection of equipment should be the selection of specific disaster recovery mode, but it should be N +1 backup or backup MSC in POOL in the future.4.2 MSC-Server IN POOL backup instance China Unicom choose Ericsson's softswitch equipment supporting MSC in POOL backup, this article focused on somel cities which set up a MSC-Server, for example, designed the MSC in POOL backup group of network programs.After six months deployment of the MSC in POOL, the network has been operating normally, the uptake rates, paging success rates of the overall network, MSC in POOL Networking Method for the traffic, CP load, the number of users and so on are relatively balanced.And the the numbers of the swiching from Inter-out are significantly reduced , it also improve the security of network and enhance the system's capacity. Still need to resolve non-IP-based roaming yards of MSC in POOL issues and MSC in POOL integrated network management statistics.5. ConclusionFrom the discussion of this article, we can see that soft switch using in the 3G network operators a great deal of benefits, from the network stability, KPI indicators, economic benefits all have been guaranteed and promoted.