Research And Implementation Of High Availability Platform In Softswitch

The traditional telecom system's availability is more and more high with the development of telecom system, which is enough for the telecom service. But for the Softswitch of NGN, the availability is not enough. So how to implement a HA system in Softswitch equipment becomes our research focus. To give a softswitch HA platform solution, the design requirement and the basic implementation of HA platform was discussed in many ways. First, the open architecture HA solution provided by HA forum was analysed, which included hardware platform, OS, management middleware and application software. Second, the HA technologies used in the softswitch HA platform were described, and in Intel Ziatech platform, the HA technologies were dicussed in detail. Then the Intel Ziatech platform was compared with the Motorola MXP. Third, the key technologies needed by HA management middleware became the emphasis. The related technologies included System State Module, Stream Control Transmission Protocol, Heartbeat Detection, Error Log, Core Dump, Dynamic IP Binding, XML Language and System Service Interface. Last, the implementation of HA management module and fault management module were dicussed in detail. Furthermore the architecture, main body and interface of the two modules were analysed. The Intel Ziatech platform solution and the real-time VxWorks of WindRiver were used in the implementation solution of this paper. In the HA management middleware implementation, the fault management module included fault detection and fault diagnosis. The fault detection was implemented by using Heartbeat Detection. The fault diagnosis was implemented by using Error Log and Core Dump to record and analyse the fault. The HA management module was in charge of data synchronization, HA event handle and system takeover. This module was designed as event driven mode. As the research shown, the event driven mode was the best selection for the complex HA management middleware. Event manager was the main body of HA management module, and it dealed with all the events which were reported to the HA management module by other modules, and notified the HA management commands. Now this solution could satisfy the basic requirement of HA management middleware, and it had good expansibility and maintenance.