Analysis of SDN Contributions for Cloud Computing Security Cloud infrastructures are composed fundamentally of computing, storage, and networking resources. In regards to network, Software-Defined Networking (SDN) has become one of the most important architectures for the management of networks that require frequent re-policing or re-configurations. Considering the already known security issues of Cloud Computing, SDN helps to give fast answers to emerging threats, but also introduces new vulnerabilities related to its own architecture. In this paper, we analyze recent security proposals derived from the use of SDN, and elaborate on whether it helps to improve trust, security and privacy in Cloud Computing. Moreover, we discuss security concerns introduced by the SDN architecture and how they could compromise Cloud services. Finally, we explore future security perspectives with regard to leveraging SDN benefits and mitigating its security issues.