SDN: prospects and challenges -Analysis of network operation engineering

The Internet has become the backbone for a wide variety of value-added services. As the connectivity requirements of these services are both numerous and varied, their engineering, deployment and operation are increasingly complex, often requiring a very high level of technical expertise. This is exacerbated by the wide variety of protocols and tools available to provide such services, and by the need for fixed/mobile convergence in particular. Simplifying the engineering and operation of these multi-service, multi-protocol, multi-technology network environments has become one of the main technical challenges facing service providers. Such a challenge can be met by the intelligent, combined activation of various techniques, including dynamic resource allocation techniques, as well as techniques for dynamically negotiating the parameters of a network service between a customer and the service provider, leading to automated service production procedures. Today, all these techniques and their combined activation are grouped under the term SDN (Software-Defined Networking). This article aims to clarify the SDN landscape.

This article, devoted to a critical and reasoned analysis of SDN techniques, is organized as follows:

• a reminder of the ecosystem of communication networks and their characteristics, with particular emphasis on the variety and complexity of the network services they support or will have to support (§ 1 );

• functional analysis of the techniques implemented by SDN architectures and definition of what the term SDN covers (§ 2 );

• issues and difficulties raised by the introduction of SDN techniques (§ 3...