The present invention is aimed at techniques for detecting the "partial
loss" of an upper layer frame. One technique envisions a detection
platform adapted to determine whether a packet is a final packet for a
particular upper layer frame. A comparator platform then compares packets
received free of transmission errors with variables indicative of whether
all received packets in the particular upper layer frame have been
received correctly when a final packet is detected. A transmission
platform then sends a signal indicative of whether the packets received
without transmission errors constitute the particular upper layer frame
so that lost packets can be retransmitted quickly.