Open RAN is a telco architecture for disaggregating the Radio Access Network into interoperable components connected by open interfaces.
In O-RAN, the major building blocks are:
- O-RAN SMO: service management and orchestration for O-RAN functions and O-Cloud resources.
- Non-RT RIC: non-real-time RAN intelligent controller, usually hosted in or next to the SMO.
- Near-RT RIC: near-real-time RAN intelligent controller for control loops around 10 ms to 1 s.
- O-CU: O-RAN central unit.
- O-DU: O-RAN distributed unit.
- O-RU: O-RAN radio unit.
- O-Cloud: cloud infrastructure used to host O-RAN network functions.
Open Interfaces
- O-RAN A1 Interface connects the Non-RT RIC to the Near-RT RIC for policy, enrichment information, and ML model management.
- O-RAN E2 Interface connects the Near-RT RIC to E2 nodes such as O-CU and O-DU functions.
- O-RAN O1 Interface connects the SMO to O-RAN managed functions for FCAPS management.
- O-RAN O2 Interface connects the SMO to the O-Cloud for cloud infrastructure management and orchestration.
- O-RAN R1 Interface exposes services from the Non-RT RIC and SMO to rApps.
- O-RAN Open Fronthaul Interface connects the O-DU and O-RU.
3GPP interfaces such as F1, E1, X2, and Xn are also used in O-RAN deployments, but the O-RAN-specific open interfaces above are the ones most associated with multi-vendor programmability and management.
See also
Sources
- O-RAN ALLIANCE
- Understanding O-RAN: Architecture, Interfaces, Algorithms, Security, and Research Challenges
Anki
id: open-ran-definition deck: Computer Science::Infrastructure::Telco tags: telco oran ran
Q: What is Open RAN? A: Open RAN is a telco architecture that disaggregates the radio access network into interoperable components connected by open interfaces.