OSA Open Service Access
OSA (Open Services Access) is a joint initiative between the 3GGP, ETSI and the Parlay Group which is designed to facilitate the design and implementation of service architectures in mobile networks. OSA services have an open API (Application Programming Interface) termed Parlay, which developers can use as the basis for server design. In the IMS (IP Multimedia Subsystem), OSA servers may require a SCS (Service Capability Server) in order to support integration with a SIP (Session Initiation Protocol) based network.
