A method, apparatus and computer-readable medium for transmitting a medium access control (MAC) protocol data unit (PDU) including one or more MAC service data units (SDUs) of a logical channel; and transmitting a first type of MAC subheader including or excluding first logical channel identifier (LCID) information and including or excluding first length information, wherein a first size of the first LCID information is equal to or smaller than a second size of second LCID information of a second type of MAC subheader that is different than the first type of MAC subheader, and a third size of the first length information is equal to or smaller than a fourth size of second length information of the second type of MAC subheader.