SBC or Session Border Controllers are devices that are regularly used in VoIP (Voice over Internet Protocol) networks in order to gain control through the signaling involved in the setting up, tearing, and conducting of media streams down the lines for telephone calls and other communications used in interactive media.
The early implementations of SBCs were mainly focused on the borderline in between two service network providers in a peer environment. The role has currently stretched in order to include certain deployments existing in the access of a service provider’s network, as well as a backbone network in order to offer service to enterprise and/or residential customers.