1. A method for communicating at a terminal in a communication system, the method comprising:receiving, from a higher layer, information related to an uplink resource;
identifying whether there is no data to be transmitted based on the uplink resource;
identifying a type of the uplink resource; and
determining not to generate a medium access (MAC) protocol data unit (PDU) based on identifying (i) that there is no data to be transmitted and (ii) the type of the uplink resource,
wherein the type of the uplink resource comprises a first type mapped to a cell radio network temporary identifier (C-RNTI) associated with a configured uplink grant.