itate the management of traffic load between NR and LTE transmission points and it may have a better flow control across the split. The ARQ functions located in the CU may provide centralization gains. The failure over transport network may also be recovered using the end-to-end ARQ mechanism at the CU. This may provide more protection for critical data and control-plane signaling. The DUs without RLC functions may handle more connected mode UEs as there is no RLC state information stored and hence no need for UE context. Furthermore, this option may facilitate imple- mentation of the integrated access and backhaul to support self-backhauled NR trans- mission points. It was argued that this option may be more robust under non-ideal transport conditions since the ARQ and packet ordering are performed at the CU. This option may reduce processing and buffering requirements in the DUs due to absence of ARQ protocol. This option may provide an efficient way for implementing intra-gNB mobility. Nonetheless, this option is more prone to latency compared to the option with ARQ in the DUs, since retransmissions are susceptible to transport network latency. In an alternative implementation, the lower RLC functional group may consist of transmitting side of RLC protocol associated with downlink transmission and the higher RLC functional group may comprise the receiving side of RLC protocol, which are related to uplink transmission. This functional regrouping is not sensitive to the trans- mission network latency between the CU and the DU and uses interface format inher- ited from the legacy interfaces of PDCP-RLC and MAC-RLC. Since the receiving side of RLC protocol is located in the CU, there would be no additional transmission delay of PDCP/RLC reestablishment procedure when submitting the RLC SDUs43 to PDCP. Furthermore, this alternative does not impose any transport constraint, for example, A service data unit is a specific unit of data that has been passed down from an open-system interconnection layer to a lower layer