M4 SBC is a Class 4 Softswitch with in-built billing, intelligent routing, DID management, and switching (transcoding) functionality. Telecommunication service providers use M4 to grow their voice business by automating their key operations, such as billing, routing, rate management, reporting, invoicing, and integrations through API. M4 can be used for these business models: SIP trunking, call origination and termination, wholesale transit, A-Z routes, and selling CC (call center) traffic.