1. A wireless transmit/receive unit (WTRU) comprising a processor configured to:receive a first physical downlink control channel (PDCCH) transmission, wherein the first PDCCH transmission indicates a release of a downlink persistent resource;
transmit a positive acknowledgement based on receiving the first PDCCH transmission that indicates the release of the downlink persistent resource;
receive a second PDCCH transmission, wherein the second PDCCH transmission indicates a release of an uplink persistent resource; and
transmit a medium access control (MAC) control element (CE) based on receiving the second PDCCH transmission that indicates the release of the uplink persistent resource.