Often a softswitch is implemented to switch calls using voice over IP (VoIP) technologies,[1] but hybrid systems exist.
Such locations have high capacity connections to carry telephone calls or digital communication to other switching centers.
Access devices to the services of a softswitch range from large media gateways with high port density to integrated access devices (IAD) at office locations, to small analog telephone adaptors (ATA) which provide just one RJ11 telephone jack to a residence.
At the turn of the 21st century with IP Multimedia Subsystem (IMS), the softswitch element is represented by the media gateway controller (MGC) element, while the term softswitch is rarely used in the IMS context, where it is called an access gateway control function (AGCF).
Class 5 softswitches are characterized by additional services for end-users and corporate clients such as IP PBX features, call center services, calling card platform, types of authorization, QoS, Business Groups and other features similar to other Class 5 telephone switches.