  IPv6 Routing Protocol for Low-Power and Lossy Networks (RPL) is the standard
network layer protocol for achieving efficient routing in IPv6 over Low-Power
Wireless Personal Area Networks (6LoWPAN). Resource-constrained and non-tamper
resistant nature of smart sensor nodes makes RPL protocol susceptible to
different threats. An attacker may use insider or outsider attack strategy to
perform Denial-of-Service (DoS) attacks against RPL based networks. Security
and Privacy risks associated with RPL protocol may limit its global adoption
and worldwide acceptance. A proper investigation of RPL specific attacks and
their impacts on an underlying network needs to be done. In this paper, we
present and investigate one of the catastrophic attacks named as a copycat
attack, a type of replay based DoS attack against the RPL protocol. An in-depth
experimental study for analyzing the impacts of the copycat attack on RPL has
been done. The experimental results show that the copycat attack can
significantly degrade network performance in terms of packet delivery ratio,
average end-to-end delay, and average power consumption. To the best of our
knowledge, this is the first paper that extensively studies the impact of RPL
specific replay mechanism based DoS attack on 6LoWPAN networks.
