Cloud or centralized radio access network (C-RAN) sites comprise less than half of all network deployments today, but C-RAN will capture the majority of deployments by 2022, according to data from Rethink Research, cited by Nokia. C-RAN site deployments are currently growing at a 23% compound annual growth rate, according to the analyst firm.

5G requires a nearly complete overhaul of existing network infrastructure, and operators around the world are in the process of meeting that need, according to Nokia. C-RAN, which consists of a centralized baseband unit, remote radio unit networks, and a transport network or fronthaul that provides a connection layer between those units, is a critical component of that effort.

This rise in C-RAN is also running in parallel with a dramatic decline in traditional or distributed RAN sites, according to the projection. Those traditional RAN site deployments have been dropping off since 2017 and will represent less than 15% of all deployments by 2025.

By increasing the proximity of cloud data centers to networks, operators are unlocking multiple benefits, according to Arnett Thomas, director of 5G/4G optical networking and cloud packet at Nokia. Those benefits include: faster deployments and cell densification; improved network performance and reliability; lower long-term opex; and new partnerships and revenue streams.

C-RAN and data centers need to evolve to multi-access edge computing to support 5G technology and deployments, he explained in a blog post. “Perhaps the most valuable dimension of 5G will be the ability to provide ultra-reliable low latency networking from human to machine and machine to machine,” he wrote.

“By placing RAN functions and applications closer to the end users, at an edge data center for example, distance and therefore latency is reduced.” Some 5G-enabled services, including autonomous vehicles, factory automation, remote medicine, and the collection of network performance analytics, will require latency as low as 1 millisecond, which represents a reduction of roughly 1,000% from latency delivered in 4G LTE networks.

To achieve that goal, data centers need to be located closer to cell sites and this is driving a new role for those facilities as conduits for edge computing, Thomas added. “Instead of sending the data to a centralized data center and/or cloud for processing, the network edge analyzes, processes, and stores the data based on content and service level requirements by the end users,” he wrote.

This also enables operators to evolve traditional physical network functions to the cloud as virtual functions, Thomas explained. “Demand for full 5G level enhanced features such as [ultra-reliable low latency] will really drive growth in edge data centers. In the next few years, we will likely see a mix of 'far edge,' 'edge,' and 'core' data centers located in many areas to support the diverse mix of 5G services.”