  The Internet of Things (IoT) has been growing rapidly in recent years. With
the appearance of 5G, it is expected to become even more indispensable to
people's lives. In accordance with the increase of Distributed
Denial-of-Service (DDoS) attacks from IoT devices, DDoS defense has become a
hot research topic. DDoS detection mechanisms executed on routers and SDN
environments have been intensely studied. However, these methods have the
disadvantage of requiring the cost and performance of the devices. In addition,
there is no existing DDoS mitigation algorithm on the network edge that can be
performed with the low-cost and low performance equipments. Therefore, this
paper proposes a light-weight DDoS mitigation scheme at the network edge using
limited resources of inexpensive devices such as home gateways. The goal of the
proposed scheme is to simply detect and mitigate flooding attacks. It utilizes
unused queue resources to detect malicious flows by random shuffling of queue
allocation and discard the packets of the detected flows. The performance of
the proposed scheme was confirmed via theoretical analysis and computer
simulation. The simulation results match the theoretical results and the
proposed algorithm can efficiently detect malicious flows using limited
resources.
