 control (RRC) functions in standalone and non-standalone NR operation. Services Functions Differences With LTE RRC standalone Standalone Architecture Architecture System Broadcast of minimum information system information Broadcast of other system Introduction of on-demand information and area provision Connection Bearer and cell settings Introduction of split SRB and control direct SRB Connection establishment Introduction of with the core network RRC_INACTIVE state Paging Introduction of RAN level paging Access control Introduction of unified access control Mobility Handover Cell selection/reselection Measurement Downlink quality Introduction of beam measurements/reporting measurements Cell identifier measurement/reporting a 'Split SRB is a bearer for duplicating RRC messages generated by the master node for terminals in dual connectivity scenar- ios and transmitting via the secondary node. Direct SRB is a bearer whereby the secondary node can send RRC messages directly to the terminals in dual connectivity scenarios. Table 2.1 shows the functional classification of NR RRC, the relevance of each function to standalone and non-standalone operation, and the similarities and differences with the LTE RRC functions. SRBs are defined as radio bearers that are used only for the transmission of RRC and NAS messages. More specifically, the new radio has specified four types of SRBs which includes SRBO for RRC messages using the CCCH logical channel; SRB1 for RRC messages which may include a piggybacked NAS message, as well as for NAS messages prior to the estab- lishment of SRB2 using DCCH logical channel; SRB2 for NAS messages using DCCH log- ical channel (SRB2 has a lower priority than SRB1 and may be configured by the network after security activation); and SRB3 for specific RRC messages when UE is in EN-DC mode using DCCH logical channel. In the downlink, piggybacking of NAS messages is used only for bearer establishment/modification/release. In the uplink, piggybacking of NAS messages is used only for transferring