4.2　CS Domain Nodes

4.2.1　CS core network nodes in a WCDMA network shall include（G）MSC Server，VLR，（G）MGW，SG，GMSC，HLR，AuC，CMN，TMSC and TMSC SERVER.

4.2.2　MSC Server and VLR deployment shall abide by the following principles:

1　MSC Servers should be deployed in a centralized manner.Multiple small-traffic local networks may share one set of MSC Server.MSC Servers shall be centrally deployed in high-traffic cities or provincial capitals with strong technical and maintenance competence，better transmission resources and IP bearer network backbone nodes.

2　MSC Server shall be deployed with VLR.MSC Server shall have the functions of SSP.

3　MSC Server should be provided with a security backup mechanism.High-capacity single MSC Server shall be equipped with necessary disaster recovery measures.

4　The capacity configuration of MSC Server shall satisfy the local and roaming subscribers traffic with consideration of practical processing reservation.

5　2G and 3G under the same MSC Server should cover the same area.

4.2.3　MGW deployment shall abide by the following principles:

1　MGWs should be distributed at required local networks based on traffic.During the initial stage of WCDMA network construction，several local networks may share one MGW whose quantity is to be increased according to future traffic growth.

2　MGW shall be deployed at a bureau location with rich transmission and IP bearer network resources.

3　MGW shall be deployed at the same bureau location as that of RNC.

4.2.4　SG deployment shall abide by the following principles:

1　SG should be integrated into MSC Server or MGW.

2　When independent deployment of SGs is necessary，they shall be configured in pairs.

4.2.5　GMSC（or GMSC Server+GMGW）deployment shall abide by the following principles:

1　For telecom operators with gateway exchange installed in existing networks，GMSC may share the same exchange，or，new gateway exchange should be constructed with softswitch equipment.

2　GMSC Servers should be deployed with local network.Multiple small-traffic local networks may share one set of GMSC Server.The deployment shall be placed in provincial capital or high-traffic city with strong technical and maintenance competence，better transmission resources and IP bearer network backbone nodes.

3　GMSC（GMSC Server）should be deployed in pairs，and all GMSCs shall have the functions of SSP.

4　GMGW should be deployed with local network as unit，and shall be at a bureau location where there are good conditions for inter-transmission with other telecom operators.

4.2.6　HLR deployment shall abide by the following principles:

1　HLR shall be combined with AUC，and large-capacity equipment should be adopted；

2　One or multiple HLRs may be deployed for one local network according to the number of subscribers，or multiple small-traffic local networks may share one HLR；

3　A reasonable disaster backup mechanism shall be considered for HLR.

4.2.7　CMN deployment shall abide by the following principles:

1　When softswitch core network has a larger scope，CMN nodes shall be installed on the network to transfer BICC signaling messages between differen（tG）MSC Servers；

2　During the initial stage of network construction，CMN equipment may be deployed by large area，and should be deployed by province as CMN quantity increases in the growth of traffic；

3　CMN shall be deployed at a bureau location with rich transmission and IP bearer network resources，supported by sufficient consideration of system security and reliability；

4　CMN should be deployed in pairs，and should be integrated into TMSC Server.

4.2.8　TMSC（or TMSC Server+TMGW）deployment shall abide by the following principles:

1　Telecom operators that have TMSC（or TMSC Server+TMGW）equipment in the existing network may use the existing equipment to switch over voice service；

2　Softswitch equipment should be used in newly built toll tandem networks，it is no longer necessary to build TDM equipment；

3　TMSC Server should be deployed by large area，and should be deployed by province in provincial capital as TMSC Server quantity increases in the growth of traffic；

4　TMG should be deployed by province and shall be placed at provincial capitals or high-traffic cities with better transmission resources and IP bearer network backbone nodes；

5　TMSC Server and TMG equipment shall be deployed in pairs so as to share traffic loads；

6　TDM toll tandem network and softswitch toll tandem network should bear load sharing in proportion with WCDMA toll traffic.

4.2.9　STP deployment shall abide by the following principles:

1　Provincial HSTP and LSTP may be deployed by signaling traffic；

2　STP equipment shall take full use of existing network STP equipment.New STPs shall be deployed in pairs at separate bureau locations.STP deployment shall comply with provisions prescribed in Specifications of engineering design for No.7 signaling network YD/T 5094.