Cluster-based flow control in hybrid software-defined wireless sensor networks

Qingzhi Liu,Long Cheng,Renan Alves,Tanir Ozcelebi,Fernando Kuipers,Guixian Xu,Johan Lukkien,Shanzhi Chen

doi:10.1016/j.comnet.2020.107788

Abstract

Software-defined networking (SDN) is a cornerstone of next-generation networks and has already led to numerous advantages for data-center networks and wide-area networks. However, SDN is not widely adopted in constrained networks, such as Wireless Sensor Networks (WSN), due to excessive control overhead, lossy medium, and in-band control channels. Therefore, a key challenge to enable Software-Defined Wireless Sensor Networks (SD-WSN) is to reduce the number of control messages required to configure the data plane. In this paper, we propose a cluster-based flow control approach in hybrid SDNs. Our approach is hybrid in the sense that it takes advantage of distributed legacy routing and centralized SDN routing. In addition, it makes a trade-off between the granularity of flow control and the communication overhead induced by the SDN controller. The approach partitions a network into clusters with minimum number of border nodes. Instead of handling the individual flows of each node, the SDN controller only manages incoming and outgoing traffic flows of clusters through border nodes, while the flows inside each cluster are controlled by a distributed legacy WSN routing algorithm. Our proof-of-concept implementations in both software and hardware show that our approach is efficient with respect to reducing the number of nodes that must be managed and the number of control messages. In comparison to benchmark solutions with and without clustering, our solution reduces communication costs for flow configuration in an SD-WSN at least by 27% and at most by 88% respectively, without degrading packet delay nor delivery rate.

Highlights

Software-Defined Networking (SDN), in comparison to traditional networking, provides improved flexibility and reduced complexity when it comes to flow management [2,3]
Given the advantages and large-scale adoption of SDN within data-center networks and wide-area networks, a logical question is whether the same advantages can be expected when SDN is introduced within a wireless sensor network (WSN) [4]
The results indicate that control traffic grows linearly with the network size, suggesting the need for control traffic reduction mechanisms. [46] proposes a mechanism for on-line metric assessment on Software-Defined Wireless Sensor Networks (SD-WSN) systems

Summary

Introduction

Software-Defined Networking (SDN), in comparison to traditional networking, provides improved flexibility and reduced complexity when it comes to flow management [2,3]. A WSN typically consists of resource-constrained sensor nodes for monitoring the physical conditions of the environment, while the SDN paradigm provides a simple and flexible control approach to communication networks [7]. The confluence of these techniques is called Software-Defined Wireless Sensor Networks (SD-WSNs) [8,9,10].

Objectives

Methods

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Conclusion