Nokia takes O-RAN leap with 5G AirScale Cloud commercialisation

Nokia has announced that its next-generation 5G AirScale Cloud RAN (radio access network) offering, based on vRAN2.0, will be commercially available some time this year, with general availability expected in 2021.

Its first-generation 5G AirScale Cloud RAN, based on vRAN1.0 and a virtualised central unit (vCU), has been in commercial operation on a mmWave network in the US since early 2019. Since then, Nokia has evolved the technology to vRAN2.0 configuration with a distributed unit (DU) running on general-purpose processor (x86)-based computing with hardware acceleration in Layer 1 (L1).

The new vRAN2.0 system introduces a virtualised distributed unit (vDU) as well as a front-haul gateway and the result is said to be a fully cloudified and disaggregated 5G base station that provides scalability, low latency, high performance and capacity, as well as several network architecture options, to meet ever-increasing market demands.

It is set up to help operators generate revenue from new 5G services, as well as to enable flexible end-to-end network slicing, meet internet-of-things (IoT) requirements and bring the overall benefits of cloud computing to RAN.

The 5G AirScale Cloud RAN solution is built to support major architecture options, offering mobile and converged operators a choice of RAN deployments: vDU and vCU can be colocated at a central or regional edge cloud; the vDU can be decentralised to an edge or far edge cloud, or the vDU can be located at the cell site.

Nokia said such flexibility is of paramount importance due to varying topologies and transport network needs, even within the same network. The 5G AirScale Cloud RAN software runs on top of both Nokia CloudBand and third-party cloud infrastructure software stacks to provide maximum flexibility.

The system has been architected for Open RAN (O-RAN), splitting the base station into radio unit (RU), distributed unit (DU), radio access point (RAP, a combination of RU and DU), centralised unit (CU), and O-RAN compliant interfaces between these elements. It also includes the RAN intelligent controller (RIC) concept to take advantage of artificial intelligence (AI) and machine learning capabilities to optimise radio and system performance. Nokia joined the O-RAN Policy Coalition in May 2020.

Nokia said it has now successfully completed end-to-end 5G data calls in a full end-to-end system comprising Nokia Cloud Packet Core, Nokia 5G AirScale Cloud RAN in vRAN2.0 configuration with full baseband in cloud, Nokia Fronthaul Gateway, and a commercial 5G device. Both real-time and non-real-time sensitive baseband computing across vDU and vCU ran in x86-based Nokia AirFrame open edge servers and Nokia AirFrame rackmount servers.

Standard off-the-shelf Intel Vista Creek hardware acceleration was used for specific parts of the real-time sensitive L1 computing in the vDU. This, said the company, will help to boost the performance even further without impacting the fully cloud-based implementation.

Since 2018, Nokia Bell Labs has been working on the potential of using graphics processing units for hardware acceleration, and Nokia expects these so-called virtual RAN3.0 systems to become mature in 2022.

Nokia’s 5G AirScale Cloud RAN also supports the company’s end-to-end network slicing, from RAN across transport to core and is also designed to reuse the existing network assets. As a front-haul gateway, it could offer an evolution path for operators to upgrade existing CPRI-based radios to eCPRI-based AirScale 5G Cloud RAN.

It can run as a standalone unit or fully integrated with the vDU on an optimised Nokia AirFrame open edge server, which is the first x86-based product built and tailored for edge cloud and far edge cloud deployments of cloud RAN.

The upshot, said Nokia, is that with the vDU moving closer to the edge, 5G AirScale Cloud RAN could enable operators to make full use of the low-latency capabilities of 5G and enables services that benefit from such low latency and high levels of reliability, such as IoT applications.

It added that with a fully cloudified basis, it could bring business benefits from the world of cloud computing and IT and core networks to RAN. These include pooling, scalability, elasticity, agility, uniformity and automation.

Nokia said operators can also deploy other network functions and services at the edge, on top of the cloud RAN deployment. For example, this can be used for mobile or multi-access edge computing implementations that benefit from the proximity of content and processing close to the point of use.

“Cloud RAN has the potential to fundamentally transform mobile networks, making them more agile and dynamic and allowing operators to be more nimble in activating new services and revenue streams,” said Ed Gubbins, principal analyst at GlobalData.

“Nokia has been more proactive and consistent in driving cloud RAN technology than its peers, and the launch of its fully cloudified 5G AirScale Cloud RAN solution is only the latest example of its commitment.”