This report examines IP Multimedia Subsystem (IMS) and Rich Communications
Suite (RCS) to understand their history, development process, current status,
and implications for mobile network operators and their customers. IMS is a
control layer within an operator' s network that centralises customer data into
a single user profile that applications can use to authenticate customers and
deliver services to devices regardless of transmission network. Operators
seeking fixed-mobile convergence have deployed IMS components to interconnect
modern all-IP infrastructure with legacy networks. Telecoms equipment vendors
and the GSM Association have been discussing IMS since 2004, both parties
focusing their marketing messages on network efficiency and richer customer
communication. Trials with MNOs have revealed difficulties with coordinating
parties to ensure interoperability, and confusion over standards and
specifications.
As MNOs in mature markets plan for the introduction of LTE (which employs key
concepts from the IMS core), this report examines the case for and against IMS
and RCS and the reasons why IMS may be more important to MNOs and telco
equipment vendors than to developers and customers.