A transmitting apparatus and method, and a receiving apparatus and method for communicating a pack of 2,048 bytes using the digital interface in accordance with the IEEE 1394 standard. A 4-byte time stamp is added to a 2,048-byte pack of MPEG (Moving Picture Experts Group)—PS (program stream) data. Also, 124 bytes of padding data is added to this pack in order that the overall byte length of data be a multiple of 16. Then the data is divided into a number of fractions which is a multiple of 2 (e.g., 32), thereby being converted into a number of data blocks equal to the number of fractions. Each data block has a byte length of a multiple of 4 (e.g., 68 bytes). A CIP header and the like are added to a predetermined number of the data blocks to form a packet.