Cellular Industry Works Towards Ending CPRI Vendor Lock-In with Open RAN Alternatives

"It is CPRI that handles the connections between the signal-processing equipment (called baseband, in the industry) and the radios in what operators call the 'fronthaul' part of the network," Explains Iain Morris. "But there are so many variables with any CPRI implementation that operators are forced to work in one vendor's system. It is effectively a proprietary tool."

Light Reading’s international editor Iain Morris has published a piece on open radio access networks (RANs) and the effort – and disagreements – surrounding how best to replace the Common Public Radio Interface (CPRI) and its tendency towards vendor lock-in.

“It is CPRI that handles the connections between the signal-processing equipment (called baseband, in the industry) and the radios in what operators call the ‘fronthaul’ part of the network,” Morris explains in his piece, entitled Open Conflict Over Open RAN. “But there are so many variables with any CPRI implementation that operators are forced to work in one vendor’s system. It is effectively a proprietary tool. Ending this ‘lock-in’ meant coming up with an open alternative to CPRI that would accommodate new demands for network design.”

The issue: agreeing on what the replacement for CPRI should look like, and at what layer of the network the functional split should take place: the high-layer Option 2 or low-layer Option 7, with proponents of the first claiming that pushing network functions into the radio hardware will reduce transport costs while those in favour of the latter claim that removing as much functionality from the radios as possible is the best option for reducing vendor lock-in and providing an environment where white-box off-the-shelf hardware can flourish.

The promotion of a commoditised environment with full cross-vendor compatibility is at the heart of Lime Microsystems’ efforts in the cellular telecommunications field. CPRI, with its promotion – intentional or otherwise – of vendor lock-in, has been a stranglehold on the industry for too long; a more open approach is required, as exemplified by Lime’s work on commodity hardware running open-source software – a mixture which has proven its worth in numerous other industries from embedded electronics up to supercomputing – with the LimeNET family, including newly-announced LimeNET Micro, and partnerships on in-the-field projects including the Telecom Infra Project CrowdCell system. Combined with an ‘app store’ system which allows one-click deployment of software infrastructure, these initiatives – and those of Lime’s partners and colleagues in the industry – will be key to bringing the proprietary telecoms market the same benefits as so many other commoditised markets have enjoyed.

Morris’ full piece, which includes comment from parties on both side of the open RAN discussion, is available now on Light Reading.