Open RAN disaggregates the RAN into main 3 components as below:
? Upper Layer Split Central Unit (CU)
• Logical node that includes a portion of the eNB/gNB functions as defined by split option 2 (PDCP RLC).
• CU can support many O-DUs.
? Lower Layer Split Distributed Unit (DU)
• Logical node that includes a portion of the eNB/gNB functions as defined by split option 7-2x.
• O-DU controls the operation of a number of O-RUs.
?O-RAN Radio Unit (RU).
• Physical node that includes a portion of the eNB/gNB functions as defined by split option 7-2x.
• Real-time aspects of control & user plane communication with the O-RU controlled by the O-DU.
? VIAVI Solutions