Network virtualization technology allows the creation of virtual networks that reflect the requirements of various services and distribute resources of a physical network among virtual tenants. Recently, the virtualization of physical networks through software-defined networking technology has become a popular method. OpenVirteX is a softwaredefined networking-based network virtualization platform that can create multiple virtual and programmable networks on top of a single physical infrastructure and provide full isolation of each virtual tenant. However, some shortcomings persist in OpenVirteX, one of which is the lack of a mechanism to distribute physical network resources efficiently among the virtual tenants. In this article, we propose a novel quality-of-service management mechanism, based on the single rate three color marker proposed by the Internet Engineering Task Force. This mechanism employs two new token buckets, called global token buckets, which are used to collect idle tokens from each virtual network. Furthermore, a resource manager can redistribute the collected tokens among the virtual networks according to their weights. Finally, our work achieves a maximum improvement of approximately 1.6 times over the performances of previous mechanisms. Software-defined networking, network virtualization, quality of service, autonomic network, single rate three color marker Date Creative Commons CC-BY: This article is distributed under the terms of the Creative Commons Attribution 3.0 License Software-defined networking (SDN) is an emerging architecture that is dynamic, manageable, costeffective, and adaptable, making it ideal for the highbandwidth dynamic nature of present-day applications. 2 The core concepts of SDN 3 can be summarized as follows: (1) SDN decouples the control plane from the data plane so that network elements can concentrate on handling the traffic and (2) SDN consolidates the control plane so that a single software control program controls the data plane of multiple network elements. Figure 1 illustrates the difference between a legacy network infrastructure and an SDN infrastructure. Namely, in the legacy network infrastructure, the plane responsible for packet forwarding (i.e. the data plane) and the plane responsible for routing (i.e. the control plane) are integrated into a single network element. In this infrastructure, because all of the functions are dependent on the real hardware, it is almost impossible for network administrators to change the behavior of the network core unless the network administrators alter the devices' configuration manually. In contrast, the SDN infrastructure separates the control plane from all network elements and integrates them into a centralized server, which is called the controller. Furthermore, it provides a set of well-defined protocols and application programming interfaces (APIs) for the communication between the controller and the network elements, which allows administrators to customize the network through software applications running at the controller. This feature provides network administrators with a new method for controlling and managing the entire network more easily and it is not necessary to alter the devices' configuration manually, which greatly reduces the costs of network management. At present, the typical and de facto standard protocol for communication between the controller and the SDN elements is OpenFlow. 4 OpenFlow was developed by Stanford University and initially used for research. Now, it has become an open standard that can be freely developed or implemented. An outstanding feature of SDN is flexibility. To
Shi and Chung REF proposed a solution to achieve QoS in SDN by marking data-plane packets and management at the control-plane.
A traffic-aware quality-of-service control mechanism for software-defined networking-based virtualized networks
International Journal of Distributed Sensor Networks
Computer Science