May 28, 2020
Until lately, the IP Multimedia Subsystem was primarily used for delivering Voice and Video-based services over IP networks such as VoLTE, RCS, etc. However, being access independent, IMS can also be connected to 5G core now to provide Voice over 5G capabilities and also allow roaming features over 5G/LTE. It naturally needs to be tweaked for specific requirements like supporting virtualized nodes, cloud-native applications, network slicing, etc. for easy integration with 5G networks.
IMS requires to be virtualized and cloud-ready to make the 5G incorporation smoother. As of now, IMS nodes are not as flexible for various multimedia services and require much longer deployment cycles. It is also important to note that the protocols used within IMS nodes like SIP and Diameter are very old and hence, a more conventional approach is required for 5G networks which are based on RESTful APIs and do not use multiple protocols. 5G nodes have the ability to be developed, deployed, managed, integrated and auto-scaled due to the use of SDN/NFV and cloud collaboration. This is not the case for IMS systems, thus, some operators have already shifted to virtualized network functions from their traditional IMS nodes.
5G systems support a range of services and rely and on edge computing, network slicing, and SBA to manage essential resources, reduce latency and improve throughput. Many 4G operators have already moved to virtualized EPC and IMS nodes and included the CUPS feature for user and control planes so as to move to 5G deployments in a more comfortable and cost-efficient way. Moreover, they have an advantage with their existing cloud-based, virtualized networks as they can easily deploy a 5G network integrated with IMS including features such as SBA, edge computing and the like to enable FWA, eMBB and other use cases.
Hence, IMS systems have the capability to be incorporated into the 5G world but they need to be adapted to the latest enhancements so as to fit with 5G networks.