Simulative investigation of intermediate checksum schemes in the presence of deadlines

Almost all automatic repeat request (ARQ) protocols rely on checksums to let the receiver decide about the presence of transmission errors. If the checksum is wrong a retransmission takes place. In case of transmission errors often only a few bits are erroneous, but in a frame retransmission all bits are transmitted again, including the correct ones. This paper introduces the so-called intermediate checksum framing scheme, which attempts to rescue most of the correct bits and to restrict retransmissions only to those parts of a frame where bit errors actually occurred. We specifically consider the case where a deadline is associated to packets and the number of retransmissions is bounded.