1. Implementing signaling gateway functions. The pinch boards that attached on the MSPF, receives signaling from TDM switching boards and then deals with it at TDM level, and then the MSPF adapts TDM signaling to IP packets. 

2. Implementing the core function of a signaling gateway by M3UA//M2UA/V5UA/IUA adaptation on signaling, and forwarding adapted messages to the MGC. 

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