What is a RAN Intelligent Controller (RIC)?

RIC is a cloud software responsible for controlling and optimizing baseband communication functions in RAN

RIC is a key element in the management of 5G network functions such as network sharing, high bandwidth applications, low latency, priority communications and more.

The intelligent RAN controller (RIC) is a key component of an open RAN architecture. The RIC architecture includes a Distributed Unit (DU) software function, a stack of protocols with multiple RAT CUs, a near-real-time RIC, and an orchestration / NMS layer with an unreal-time RIC.

The functionality of RIC is implemented as Virtual network functions (VNFs) or containers in cloud computing. These software features interact with the radio monitor (RU) hardware for maximum RAN optimization and efficiency.

RIC design

RIC includes both non-real-time (non-RT) and near-real-time (near RT) components, both of which control separate RAN functions. RIC without RT manages events and resources with a response time of one second or more. The nearby RT RIC also manages events and resources that require a faster response of up to 10 milliseconds (ms). A non-RT RIC is centrally located, while a nearby RT RIC can be located centrally or at the edge of the network.

RIC, which is not RT, operates from RIC’s Service Management and Orchestration (SMO) platform, so it handles lifecycle management for all network elements, configuration management, and many other basic network functions. Non-RT RIC optimizes RAN functions by providing policy-based guidance, model management, and RIC function enrichment information close to RT.

The nearby RT RIC controls the RAN infrastructure at the end of the cloud.

rApps are specialized micro-services operating on RIC outside RT that provide basic control and management functions and functionality. xApps are hosted on the nearby RT RIC.

RIC specifications and management

The features and functionality of RIC – and RAN disaggregation in general – are described in 3GPP Edition 15. O-RAN alliance manages several technical working groups responsible for the design of various elements of the Open RAN specification.

The RIC specification guide falls under the auspices of O-RAN Workgroups 2 and 3. These are the RAN Intelligent Controller in real time and the A1 Interface Workgroup and the RIC and E2 Interface Workgroup in near real time, respectively.

Intelligent RAN controller (RIC) in the news

The O-RAN Alliance has published a set of Open the RAN technical specifications in October, which includes the initial version of its Intelligent Controller (RIC) architecture in unrealistic time.

VMware announces RIC for its Telco Cloud Platform. VMware RIC uses the Intel FlexRAN reference architecture. VMware expects to release VMware RIC in 2022 after an increase in developers in late 2021.

NEC and NTT Docomo announced cooperation with RIC in June. The two companies said they seek to reduce RAN’s operating costs, improve productivity and reduce energy consumption through the use of RIC software. RUs will meet the O-RAN fronthaul interface specifications defined by the O-RAN Alliance and will be compatible with base station equipment from various vendors.

Deutsche Telekom and the Open Network Foundation (ONF). starts a software-defined WAN (SD-WAN) trial period in Berlin. The test integrates components from eight companies: AirHop, Edgecore, Facebook, Foxconn, Intel, Radisys, Supermicro and Wiwynn. In addition, the Telecom Infra (TIP) project is involved by providing hardware and equipment from the TIP Community Lab in Berlin, hosted by Deutsche Telekom.

The live 4G / 5G trial includes horizontally disaggregated hardware (separate RU, DU, and CU units), as well as vertically disaggregated software components, including near-real-time open source RIC (nRT-RIC) and xApps coming from SD- RAN of the ONF project.