There is a good reason why the only at-scale Open RAN deployments are currently by greenfield operators such as Rakuten Mobile and Dish Network. It is clearly far harder to move to a new architecture with open interfaces for an operator that has invested huge sums, in very recent times, in building a conventional, non-virtualized network from a traditional vendor, and also put in all the effort to integrate that new RAN with legacy 2G/3G/4G systems(or to replace the whole thing with a multi-RAT SingleRAN). Many operators are keen to introduce RAN elements with open interfaces as they make two significant next steps in 5G – one, to introduce virtualized RAN for the first time; and two, to expand the…