SDX architectures: A qualitative analysis

A novel internetworking paradigm, software-defined exchange (SDX), allows multiple independent administrative domains to share computing, storage, and networking resources. Although the term SDX is very recent, the concept has already been used by many distinct disciplines. For example, cloud-computing researchers use it to add network virtualization resources to their inter-clouds, while networking researchers use it to insert SDN technologies into the networking exchange infrastructure. Despite the different uses, the efforts of the various disciplines that share networking resources converge to a single poing enabled by the virtualization and the separation of control and data planes. This paper presents a survey of the most relevant SDX studies from various research areas, focusing on their architectures. The paper defines a taxonomy for the SDX, provides generalized architecture models, and concludes by presenting a qualitative analysis of the architectures that focuses on the scalability, resilience, peering technologies, and deployment of SDX.