Abstract: The present disclosure is directed to a system and method configured to implement an inter-MSC based handoff of a mobile device between a packet switched network and a mobile core network. In embodiments implementing a handoff from a femtocell to a macrocell, from the perspective of a neighboring MSC on a mobile core network, IP or VOIP information from a femtocell which is in communication with the convergence server, is perceived as having the same protocol as information which originates from a macrocell. Inversely, in embodiments implementing a hand-in to the femtocell from a macrocell, information which originates from a macrocell, which is in communication with the convergence server, would be perceived as IP or VOIP code to the femtocell. Accordingly, a target MSC in a handoff is agnostic of the fact that the mobile device entering into the macrocell was actually attached to a femtocell. Thus, embodiments of the present invention allow existing inter-MSC based handoff solutions to be leveraged.