O-RAN
Open RAN: an industry initiative promoting open, interoperable, and intelligent RAN architecture with disaggregated components (O-CU, O-DU, O-RU) and open fronthaul interfaces.
Open RAN is a reaction to a long-standing frustration: traditionally, if you bought your radio from one vendor, you were locked into that vendor for the baseband and the upgrades and the roadmap, because the interfaces between the pieces were proprietary. O-RAN's whole premise is to open those interfaces — chiefly the fronthaul between the radio and the baseband — so an operator can mix a radio from one supplier with baseband software from another.
Two ideas sit at the centre. First, disaggregation: the gNB is broken into an O-RU (radio unit), O-DU (distributed unit), and O-CU (central unit), connected by standardised interfaces, with the fronthaul defined by the 7.2x split. Second, intelligence and openness: the RIC (RAN Intelligent Controller) provides a standard home for optimisation apps, and much of the software is designed to run on general-purpose hardware. The promise is more vendor competition, lower cost, and faster innovation. The honest counterweight is integration: someone has to make multi-vendor combinations actually interwork and stay performant, and that systems-integration burden is the practical reason O-RAN adoption has been more gradual than the hype suggested.
Frequently asked questions
- Isn't all RAN already 'open' since it follows 3GPP standards?
- 3GPP standardises the air interface and the interfaces toward the core, but it left several internal RAN interfaces — notably the fronthaul between baseband and radio — open to vendor-specific implementation. In practice that meant the radio and baseband had to come from the same vendor. O-RAN Alliance specifications fill those gaps with open fronthaul (the 7.2x split) and the RIC interfaces, so different vendors’ components can be combined. So it adds openness exactly where 3GPP did not require it.
Related terms
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