In the late 20th century, fixed operators undertook the migration of their networks from TDM commutation to IP networks. By replacing their telephony switches with Softswitches and IP gateways, they could offer triple-play: Voice over IP, Internet and IPTV, at an affordable price.

Since then, 3GPP has defined an advanced telephony architecture, called IMS (IP Multimedia Subsystem), and recommends it for various types of network access: 4G in mobile network, 5G soon, but also for fixed broadband networks, such as Cable, xDSL and fiber networks.

This article describes briefly the difference between Softswitch architecture and IMS, lists the reasons and benefits for a telecom operator to migrate to IMS, and explains how we at Cirpack can help you achieve such migration.