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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.