moving functionality to the network edge, companies can add, modify, and expand services without disrupting core network functions. edge stps perform a broad range of roles in evolving telecommunications networks. they include optimizing services such as short message service (sms) for improved performance; providing precise security policies to subnetworks; preventing service interruptions during switch migrations; and connecting server-based applications to switched networks. in the latter scenario, telecommunications companies that are implementing ip subnetworks use edge stps to integrate them with their existing ss7 signaling infrastructure.