The Radio Access Network, or “RAN”, is undergoing a significant transformation. Moving away from siloed, monolithic architectures with one, or few, vendors supporting, communications services providers (CSPs) are modernizing their architectures to break free from vendor lock-in, enabling innovation and reducing costs.

Learn more about the RAN transformation here

Many CSPs start the modernization by disaggregating the radio software from the underlying hardware with virtualization. Virtual RAN (vRAN) virtualizes network functions and enables them to be controlled by software platforms using commercial off the shelf processors (COTS).

Many CSPs which virtualize their RAN are moving forward open RAN approaches. Open RAN is a methodology of disaggregating the RAN and providing open interfaces. With the open interfaces, CSPs enable innovation that will leverage RAN resources. This practice increases competition in a previously closed environment and spurs innovation across a growing ecosystem of software providers.

To help build standards around open RAN, the O-RAN Alliance created specifications to help define open RAN architectures and interfaces. The O-RAN architecture is community-developed and driven by the desire to increase intelligence and openness in RAN networks.

Each phase of the RAN modernization brings additional benefits to CSPs looking to monetize their RAN investments.

Advantages of vRAN:

• vRAN provides the ability to deploy various industry-leading vRAN functions at the best locations to serve their functional purposes, creating 5G networks with much more flexible design than the traditional RAN. This increases performance, coverage and capacity without linearly scaling the entire RAN while improving the quality of experience (QoE).
• vRAN enables consistent operability across various vRAN functions as well as network functions deployed throughout 5G networks, from the core, edge, to RAN.
• Additionally, vRAN delivers superior protection from security threats than the conventional parameter-based and reactive security approaches.
• vRAN also provides investment protection by allowing CSPs to run vRAN functions now and evolve to O-RAN using the same platform when O-RAN standards and technologies become mature.

Advantages of Open RAN:

• The highly programmable infrastructure enables dynamic responses to fluctuating demand and eliminates inefficient use of spare capacity.
• The multivendor environment encourages competition and innovation with best-of-breed solutions from different RAN vendors.
• Disaggregation of management and control planes from the vRAN functions (basically handling the data plane) allows the RAN intelligence to be managed and controlled, more centrally, by a new entity introduced in the O-RAN standards called RAN Intelligent Controller (RIC), making the RAN programable.
• The RIC’s ability to host RAN-centric applications enables new application vendors to enter the RAN market, bringing new innovation to CSPs.
• Strong relationships between RIC vendors and application vendors enhances rapid innovation propelled by an open ecosystem. The Open RAN represents a shift from traditional RAN architectures dominated by a small ecosystem toward a disaggregated, multi-vendor environment with modular elements, open interfaces, and programmable infrastructure.

FIGURE 1: The O-RAN Alliance Open RAN architecture.

For details on the elements listed in Figure 1, please download RAN Transformation for Dummies

The architectural element that ties together the complex layer of platforms and software for deploying and managing decomposed radio access networks. It manages the RAN domain.

The open RAN architecture of the O-RAN Alliance charts a course for SMO. It points toward a virtualized, containerized, disaggregated, and standardized open radio access network that supports multiple vendors and clouds by using an SMO layer to automate and optimize the RAN and its applications. Central to this architecture is the RIC.

There are two logical forms of the RIC, and each performs a different function:

• The near-real-time RIC is a distributed RIC that runs extensible microservices from third-party vendors, called xApps by the O-RAN Alliance, to manage and optimize resources for network functions.
• The non-real-time RIC is a centralized RIC that hosts rApps to do such things as collect data, build machine learning models, and send optimization policies to the near-RT RIC for execution. Both the near-real-time RIC (near-RT RIC) and the non-real-time RIC (non-RT RIC) are virtualized or containerized logical components that play a role in controlling and optimizing RAN elements and resources.

1. VMware Telco Cloud Platform RAN - RAN-optimized horizontal platform, consisting of field proven virtualization, carrier-grade CaaS, and multi-layer automation, VMware Telco Cloud Platform RAN modernizes traditional RAN. Built with purpose-built hardware equipment, the platform helps CSPs virtualize and disaggregate RAN functions to accelerate CSPs ability to offer secure 5G services while containing costs and risks.
2. VMware RIC – The RAN Intelligent Controller (RIC) abstracts the complexity of open and multivendor RAN through programmability and intelligence.

VMware RIC is part of the broader VMware Telco Cloud™ ecosystem and is charged with enabling programmability of the RAN driven by intelligence to dynamically support new applications and services.

VMware RIC is comprised of two products: VMware Centralized RIC, which is non‑real‑time, and VMware Distributed RIC, which is near‑real‑time.