1. A method of wireless communication for a first user equipment (UE), comprising:configuring, the first UE to belong to one or more device-to-device (D2D) communication groups;
configuring, at the first UE, at least a non-access stratum (NAS) protocol layer or a radio resource control (RRC) protocol layer to enable D2D communication with a second UE when the first UE is out of network coverage, wherein configuring the RRC protocol layer further comprises transitioning the RRC protocol to a D2D communication state and when configuring the RRC protocol layer, the RRC protocol layer configures a medium access control (MAC) layer to generate a MAC subheader, the MAC subheader comprising group number information that indicates a number of group identities (IDs) included in the MAC subheader, the group IDs indicating the one or more D2D communication groups to which the first UE belongs;
configuring, at the first UE, one or more protocol layers based on the configuring of at least the NAS protocol layer or the RRC protocol layer, the one or more protocol layers different from the NAS protocol layer and the RRC protocol layer; and
communicating with the second UE.