Call Controllers

Call session controllers or softswitches are critical switching elements that enable voice and multimedia calls and sessions to traverse networks, enabling a seamless user experience.  They are the core components in architectures like IMS, next generation voice over IP networks and enterprise networks.

Ribbon is the market leader in this category with four state-of-the-art and widely deployed carrier class platforms and software: C20, C15, C3 and T7000 Call Session Controllers.  These platforms and software are used by service providers to control operational expenditures, grow revenue, offer Business and Consumer VoIP services over broadband and wireless access, transform or replace costly legacy switching systems, and converge disparate mobile and fixed networks. 

Class 4 and Class 5 Switch Replacement

Ribbon’s Call Session Controllers allow service providers to grow revenue and deliver voice and IP multimedia services to their subscribers by replacing or reusing the legacy Class 4 and Class 5 switches in the network. The products also enable tandem or transit trunking and interconnect capabilities.

Legacy Switch Migration (Nortel DMS, EWSD and Others)

Ribbon’s Call Controller portfolio enables service providers to significantly consolidate and modernize their existing network of legacy switches, including Nortel DMS 10, Nortel DMS 100, DMS 200, EWSD Switch and many others, and offer all new IP services to their business and consumer subscribers.


Call Controllers Portfolio

C3 Call Session Controller

Intelligent multi-application call controller and media gateway/software control platform

C15 Call Session Controller

Carrier-grade, and compact call control & softswitch platform

C20 Call Session Controller

Carrier grade, intelligent, and advanced call session control platform for voice and multimedia


Carrier-class Class 5 switching system

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Ribbon's team of professionals are ready to answer your questions, guide you to the right solution or help you with your network design.