Monday 15 July 2019

Small Cell Forum Releases 5G FAPI API Specifications

SCF has announced the release of 5G FAPI: PHY API Specifications. In the press release titled 'Small Cell Forum Publishes Specification to Drive Unified 5G Open RAN', SCF announced:

5G FAPI Release provides common APIs to support interoperability between 5G small cell hardware components and software layers enabling interoperability and preventing fragmentation.

Small Cell Forum (SCF), the telecoms organization making mobile infrastructure solutions available to all, has published the PHY API for 5G to stimulate a competitive ecosystem for vendors of 5G small cell hardware, software and equipment. The PHY API provides an open and interoperable interface between the physical layer and the MAC layer. 3G and LTE versions are already used in most small cells today.

The specification has been developed through a successful collaboration of companies from across the small cell eco-system, including; Intel, Qualcomm Technologies, Inc., Airspan Networks and Picocom Technology.

5G FAPI is an initiative within the small cell industry to encourage competition and innovation among suppliers of platform hardware, platform software and application software by providing a common API around which suppliers of each component can compete. By doing this, SCF provides an interchangeability of parts ensuring that the system vendors can take advantage of the latest innovations in silicon and software with minimum barriers to entry, and the least amount of custom re-engineering.

Operators are looking for a radically different cost model for 5G networks, one that relies on interoperability and an open, competitive ecosystem. As networks are disaggregated, a critical interface is the fronthaul between a distributed unit (DU) for radio functions and a centralised unit (CU) for protocol stacks and baseband functions. Open specifications such as SCF’s FAPI will enable operators to mix and match protocol stacks, basebands and radios from different vendors, and realize the benefits of deploying disaggregated, virtualized RAN (vRAN) networks.

The Forum also maintains the widely adopted FAPI specifications for 3G and LTE, as well as networked FAPI (nFAPI) for LTE supporting a MAC/PHY functional split, a key enabler for virtualisation of higher layer base station functions. In 5G this split point was also identified by 3GPP and called split option 6.

The Forum’s motivation for defining nFAPI in LTE was to establish a scalable ecosystem with a converged approach to virtualization across multiple suppliers, and the continued adoption of NFV/SDN make this is even more crucial for 5G. As such, the Forum plans to expand 5G FAPI to operate across split option 6 as 5G nFAPI.

A video of presentation by Clare Somerville, Intel & 5G FAPI lead from Small Cells World is embedded below:


In an interview in The Mobile Network last December, Prabhakar Chitrapu, who chairs SCF’s TECH Group said:

“Split RAN/Small Cell architectures have seven options, as identified by 3GPP. Of these, 3GPP has focused on Option-2 (RLC-PDCP) and ORAN on Option-7.2 (PHY-PHY). Option-6 (PHY-MAC) is not being addressed by any of these organisations. SCF seeks to fill this gap.”

“The PHY-MAC interface is important for the industry because it is an interface that has been highly successful in the 4G world, where it is called FAPI and nFAPI. It is therefore considered very important that we extend these interface specifications for 5G, as 5G-FAPI and 5G-nFAPI."

“FAPI helps Equipment Vendors to mix PHY & MAC Software from different suppliers via this open FAPI interface. So, FAPI is an 'internal' interface.”

“5G-nFAPI (network FAPI) is a 'network' interface and is between a Distributed Unit and Centralised Unit  of a Split RAN/Small Cell network solution. An open specification of this interface (nFAPI) will help network architects by allowing them to mix distributed and central units from different vendors.”

ShareTechNote also provides some details about FAPI and nFAPI as described by Small Cell Forim here.

Related Documents from SCF:

No comments:

Post a Comment