The term "softswitch", despite being widely used in the telecommunications industry, doesn't really have a clear definition. Softswitch, media gateway controller, call agent, gatekeeper: These are the varied nomenclatures that have been attached to the products that perform the functions that are coming to be called softswitches. A Softswitch is typically used to control connections at the junction point between circuit and packet networks. A single device containing both the switching logic and the switching fabric can be used for this purpose; however, modern technology has led to a preference for decomposing this device into a call agent and a media gateway. The International Softswitch Consortium (ISC) is leading the charge to evolve traditional telephone networks to more efficient and feature rich softswitch-based networks.

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