Biblio

The emerging time-sensitive applications, such as industrial automation, smart grids, and telesurgery, pose strong demands for enabling large-scale IP-based deterministic networks. The IETF DetNet working group recently proposes a Cycle Specified Queuing and Forwarding (CSQF) solution. However, CSQF only specifies an underlying device-level primitive while how to achieve network-wide flow scheduling remains undefined. Previous scheduling mechanisms are mostly oriented to the context of local area networks, making them inapplicable to the cyclic traffic in wide area networks. In this paper, we design the Cycle Tags Planning (CTP) mechanism, a first mathematical model to enable network-wide scheduling for cyclic traffic in large-scale deterministic networks. Then, a novel scheduling algorithm named flow offset and cycle shift (FO-CS) is designed to compute the flows' cycle tags. The FO-CS algorithm is evaluated under long-distance network topologies in remote industrial control scenarios. Compared with the Naive algorithm without using FO-CS, simulation results demonstrate that FO-CS improves the scheduling flow number by 31.2% in few seconds.

Distributed Denial of Service attack is very harmful to software-defined networking. Effective defense measures are the key to ensure SDN security. An adaptive moving target defense scheme based on end information hopping for SDN is proposed. The source address entropy value and the flow rate method are used to detect the network condition. According to the detection result, the end information is adjusted by time adaptive or space adaptive. A model of active network defense is constructed. The experimental results show that the proposed scheme enhances the anti-attack capability and serviceability compared with other methods, and has greater dynamics and flexibility.