Access control mechanisms for d2d discovery and communication

A user equipment (UE) configured to support device-to-device (D2D) communication, the UE comprising:

• transceiver circuitry configured to receive an access-class-barring (ACB) skipping communication from a network node, the ACB-skipping communication comprising an indication that the UE is permitted to skip an ACB configuration used by the network node when the UE requests to establish a radio resource control (RRC) connection for D2D communication using a D2D resource-allocation mode (mode 1) wherein radio resources are allocated by the network node;
• and
• one or more processors configured to apply the indication when establishing the RRC connection for D2D communication to enable the UE to skip the ACB configuration.

One or more non-transitory computer-readable mediums containing instructions thereon which when executed by one or more processors perform the following:

• receiving, at a user equipment (UE), an access-class-barring (ACB) skipping communication from a network node, the ACB-skipping communication comprising an indication that the UE is permitted to skip an ACB configuration applied at the network node when the UE requests to establish a radio resource control (RRC) connection for D2D communication using a D2D resource-allocation mode (mode 1) wherein radio resources are allocated by the network node;
• and
• determining when a user equipment (UE) is allowed to establish a RRC connection for D2D communication using mode 1 based on the ACB-skipping communication.

An apparatus of a user equipment (UE), the apparatus comprising circuitry configured to support device-to-device (D2D) communication, the circuitry configured to:

• receive a fall-back communication from a network node, the fall-back communication comprising an indication that the UE is permitted to use a second D2D-resource-allocation mode (mode 2) when use of a first D2D-resource-allocation mode (mode 1) is barred by Access Class Barring (ACB) in a cell served by the network node, wherein UEs allocate radio resources in mode 2 and the network node allocates resources in mode 1;
• and
• apply the indication when the UE seeks to perform a D2D communication.