The main revisions include the following：
1.In the chapter of General Provisions，the types of voice and data services are refined and the application principles for "new technology，new materials，new techniques and new equipment" as well as the provisions on energy conservation and environmental protection are added.
2.In the chapter of Terms and Abbreviations，the explanation on the term of "core network" is added and the abbreviations used in this Code are sorted out and kept in line with the

《铁路数字移动通信系统（GSM-R）设计规范（TB10088-2015）（英文版）》：
3.1 GeneraIRequirements
3.1.1 The design of core network shall include the following contents:
1 Switching Subsystem（SSS）.
2 Intelligent Network（IN）Subsystem,
3 Core network equipment of General Packet Radio Service（GPRS）subsystem.
4 Equipment related to the packet switched（PS）domain application system.
3.1.2 The setting location of the core network equipment shall comply with the communication network planning.
3.1.3 The subscriber capacity,quantity of interfaces and processing capacity of all the subsystems of the core network shall be under unified planning and design and should satisfy the demand in the short term.
3.1.4 The bandwidth of links for interconnection between the core network equipment should satisfy the demand for the 5th year after commercial operation and should be provided with the conditions for future expansion
3.2 Switching Subsystem（SSS）
3.2.1 According to the network scale,the network structure of SSS may be designed as:
1 One-level structure of local network.
2 Two-Ievel structure of tandem network and local network.
3.2.2 The design of tandem network includes the TMSCs and the trunk links connecting these nodes and shall comply with the following provisions:
1 The whole network may be divided into several mobile service tandem areas.
2 Each tandem area should be provided with a standalone TMSC.
3 The interconnection between the TMSCs shall be in the form of a mesh network structure.
3.2.3 The local network shall be provided with the Mobile Switching Center（MSC）, Visitor Location Register（VLR）, Group Call Register（GCR）,InterWorking Function（IWF）, Gateway Mobile Switching Center（GMSC）, Home Location Register（HLR）,Authentication Center（AuC）, Acknowledgement Center（AC）,etc.,and may be provided with the Short Message Service Center（SMSC）and Equipment Identity Register（EIR）as required.
3.2.4 The setting and networking of MSC shall comply with the following provisions:
1 MSC should be set in a centralized manner with redundancy configuration.
2 The 1+1 active/standby mode or the load sharing redundancy mode may be adopted for MSC.
3 A direct link should be provided between the adjacent handover MSCs for a Base Station Subsystem（BSS）.
4 For the SSS designed with a two-level network structure,the MSC shall be connected to two home fMSCs respectively.
5 When R4 network architecture is adopted for MSC and TMSC,transmission links should be employed for the interconnection between the adjacent MSCs,between MSC and TMSC as well as between TMSCs.
……

1 General Provisions
2 Terms and Abbreviations
2．1 Terms
2．2 Abbreviations
3 Core Network
3．1 General Requirements
3．2 Switching Subsystem （SSS）
3．3 Intelligent Network （IN） Subsystem
3．4 Core Network of General Packet Radio Service （GPRS） Subsystem
3．5 Equipment Related to PS Domain Application System
4 Base Station Subsystem
4．1 Requirements for Radio Coverage
4．2 Radio Coverage Design
4．3 BTS Type and Capacity
4．4 Channel Configuration
4．5 Carrier/lnterference （C/D Ratio
4．6 Control Equipment for BTS
4．7 Antenna Pole （Tower）
5 Interconnection and Interfaces
5．1 Interconnection
5．2 Main Interfaces of GSM-R System
6 Number Planning
7 Quality of Service （QoS）
8 Mobile Station（MS）
9 Operation & Maintenance and System Support
9．1 Network Management
9．2 Signaling
9．3 Synchronization
9．4 Monitoring
9．5 Data and SIM Card Management
9．6 Special Maintenance Tools and Spare Parts
10 Power Supply Equipment
11 Operation Environment
11．1 Requirements for External Power Supply
11．2 Lightning Protection and Earthing
11．3 Buildings
11．4 Equipment Layout and Wiring
Appendix A Calculation Methods for GSM-R Main Interfaces
Normative References
Words Used for Different Degrees of Strictness