A method of data communication. The method includes transmitting a control
message identifying missing data as lost by the transmitter prior to the
expiration of a timer. The missing data may include at least one data
packet such that the control message identifies the at least one missing
data packet. The control message may include a field and/or an
acknowledge sequence number for identifying the missing data packet. The
control message also may include a packet data unit having a dummy
payload and/or a zero payload. The control message communicates to the
receiver that the transmitter has aborted the transmission and/or
retransmission of the one or more missing data packets. The control
message may be communicated to the receiver over the same data channel
used for transmitting the data packets, or alternatively, a wholly
different channel than the data channel.