Biblio

Traffic in a backbone network has high forwarding rate requirements, and as the network gets larger, traffic increases and forwarding rates decrease. In a Software Defined Network (SDN), the controller can manage a global view of the network and control the forwarding of network traffic. A deterministic network has different forwarding requirements for the traffic of different priority levels. Static traffic load balancing is not flexible enough to meet the needs of users and may lead to the overloading of individual links and even network collapse. In this paper, we propose a new backbone network load balancing architecture - EDQN (Edge Deep Q-learning Network), which implements queue-based gate-shaping algorithms at the edge devices and load balancing of traffic on the backbone links. With the advantages of SDN, the link utilization of the backbone network can be improved, the delay in traffic transmission can be reduced and the throughput of traffic during transmission can be increased.

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.