This document provides an overview of virtualization and the Nexus1000V virtual switch from Cisco. It discusses the benefits of virtualization, including efficient use of resources and lower costs. It then describes the Nexus1000V, which provides a virtual switching and security layer inside virtual machines similarly to a physical switch. The Nexus1000V uses Virtual Supervisor and Ethernet Modules to provide distributed switching and supports multiple hypervisors. It also integrates with OpenStack using the Cisco OpenStack Installer to deploy and manage the virtual switch and virtual extensible local area network.