Abstract
We consider a multiple access relay network where multiple sources send independent data
to a single destination through multiple relays, which may inject falsified data into the network. To
detect the malicious relays and discard (erase) data from them, tracing bits are embedded in the
information data at each source node. In addition, parity bits are added to correct the errors caused
by fading and noise. When the total amount of redundancy, tracing bits plus parity bits, is fixed, an
increase in parity bits to increase the reliability requires a decrease in tracing bits, which leads to a
less accurate detection of malicious behavior of relays, and vice versa. We investigate the tradeoff
between the tracing bits and the parity bits in minimizing the probability of decoding error and
maximizing the throughput in multisource, multi relay networks under falsified data injection attacks.