Evolve to 3G With GSM IP Platform
GSM IP is an important tool for delivering in-building applications successfully. It solves technical implementation challenges with a robust architecture that offers an intelligible design and networking solution.
By Casey Joseph, Tecore
Network engineers and planners continue to examine the move to 3G as they focus on integrating next-generation architecture into telecom systems. One technology that is positioned to support the evolution of wireless technologies to 3G for broadband applications is the emerging GSM Internet Protocol (IP) architecture. The technology allows for integration between IP-based corporate GSM networks, traditional circuit-switched GSM networks, and corporate PBX networks.
The latest telecom industry design trend stipulates that the newest network technologies be IP-based to carry voice, video, and data traffic. These IP-based networks position carriers for such evolving technologies as General Packet Radio Service (GPRS), Enhanced Data Rate for GSM Evolution (EDGE), and 3G.
The GSM IP architecture offers integration with both GSM networks and corporate networks (see figure). In deploying the GSM corporate switching platform solution, engineers need to install two integral network elements—a server and a gateway.
AirCore GSM IP architecture
The specialized server for IP-based GSM applications in corporate networks includes software applications for standard GSM network elements such as the mobile switching center (MSC), home location register (HLR), visitor location register (VLR), authentication center (AuC), equipment identity register (EIR), and operation & maintenance center (OMC). This setup results in a fully functional GSM network switching subsystem (NSS) residing on a corporate server.
The server can interface to base station subsystem (BSS) equipment from other suppliers via standard A-Interface over IP. Corporate end-users will be able to access and modify their service profiles through Web-based access for such tasks as changing their call forwarding numbers. In addition, the server can be connected directly to a corporate PBX through IP interface or traditional circuit-switched interface. Optionally, the transcoding and rate adaption unit (TRAU) function can be performed at the server.
The Gateway
The GSM IP platform gateway—at the heart of the system—can interface to multiple servers via an IP interface for voice and SS7 traffic. The gateway converts IP traffic from multiple servers into traditional circuit-switched interface such as C7 Integrated Services User Part (ISUP) and Integrated Services Data Network Primary Rate Interface (ISDN PRI), as well as GSM MAP for integration with the existing GSM networks and public switched telephone network (PSTN). This provides networking between multiple servers in a corporate campus and to the GSM network for seamless roaming and handover.
Here are a few benefits of the server-and-gateway approach to GSM:
- It provides low-cost, server-based mobility applications.
- The system requires only a server and software instead of large-scale switching equipment (see figure above).
- It integrates with the PBX to provide PBX features such as abbreviated dialing. If the PBX has an IP interface, then it is possible to have tighter integration between the PBX and in-building GSM.
- The system extends GSM coverage via corporate local area network (LAN) or wide area network (WAN).
- It positions the corporate network for high-bandwidth wireless applications.
With this software-based architecture, engineers, and network managers can migrate their PBX systems to IP-based systems, which means more feature-rich performance and cost-savings on both equipment and deployment.
Evolving to 3G
This same architecture can be applied to other wireless technologies such as code division multiple access (CDMA) and time division multiple access (TDMA). The platform will also enable network planners to evolve to 3G for the corporate market. Because corporate networks are IP-based, it is a good fit to deploy 3G.
The technology enables network planners to integrate GSM into a corporate LAN or WAN environment with a software-based applications server that replaces traditional switching systems. Once GSM is deployed in-building on an IP platform, the technology works well with data applications, whether they are GPRS, EDGE, or 3G.
GSM/IP Architecture Fast Facts
- Enables a wide range of applications
- Makes the evolution to IP-based packet switching architecture easier
- Features software-driven platform
- Uses standard NT server platform
- Supports multiple servers over TCP/IP
- Offers low-cost, server-based mobility applications
- Positions carriers for future high-bandwidth applications
About the Author
Casey Joseph is the chief technology officer at Tecore, 7151 Columbia Gateway Dr., Columbia, MD 21046. Tel: 410-872-6000. Fax: 410-872-6010.