Embodiments of a User Equipment (UE), Evolved Node-B (eNB) and methods of communication are generally described herein. The UE may receive a SystemInformationBlockType1 from an eNB. The UE may determine that the eNB supports Fifth Generation Core (5GC) operation if the SysteminformationBlocklType1 message includes a plmn-Identity-5GC-r15 parameter. The UE may transmit a radio resource control (RRC) connection request message to establish an RRC connection. If it is determined that the eNB supports 5GC operation, and if the UE supports 5GC operation, the UE may encode the RRC connection request message in accordance with a default new radio packet data convergence protocol (NR PDCP) configuration; and may use NR PDCP for one or more subsequent messages.