Method and system for implementing aggregate endpoints on IMS networks

A method and system are adapted to provide telephony services to aggregate endpoints on an Internet Protocol Multimedia Subsystem (IMS) network. The method includes assigning one or multiple PUIDs for surrogate registration purposes during the provisioning of the aggregate endpoint, performing reliable surrogate registration on behalf of the aggregate endpoint, allowing multiple SBCs to perform surrogate registrations independently for the same aggregate endpoint to achieve reliability, and providing reliable connection from an IMS core to the aggregate endpoints via multiple S/BCs. The system includes one or more Session Border Controllers (S/BC), at least one set of Call/Session Control Functions (CSCF), and an HSS operatively coupled together.