The document provides an overview of the IP Multimedia Subsystem (IMS) technology and its implications for the telecommunications industry, highlighting its advantages such as cost reduction, support for various types of networks, and the facilitation of new service implementations. Key drivers for the adoption of IMS include the need for operators to consolidate and offer converging services amidst competition from over-the-top (OTT) service providers, as well as the growing demand for LTE networks. The report also discusses global market trends, key vendors, and the evolution of IMS architecture and its deployments in Russia.