Extending Networking into the Virtualization Layer.

TLDR

Virtualization introduces a new network access layer on hosts that connects virtual machines, imposing requirements unmet by traditional models while offering software flexibility and well‑defined host events. We present Open vSwitch, a network switch specifically built for virtual environments. Open vSwitch provides an external interface for fine‑grained control of configuration state and forwarding, enabling isolation in multi‑tenant setups, mobility across subnets, and distributed configuration and visibility across hosts.

Abstract

The move to virtualization has created a new network access layer residing on hosts that connects the various VMs. Virtualized deployment environments impose requirements on networking for which traditional models are not well suited. They also provide advantages to the networking layer (such as software flexibility and welldefined end host events) that are not present in physical networks. To date, this new virtualization network layer has been largely built around standard Ethernet switching, but this technology neither satisfies these new requirements nor leverages the available advantages. We present Open vSwitch, a network switch specifically built for virtual environments. Open vSwitch differs from traditional approaches in that it exports an external interface for fine-grained control of configuration state and forwarding behavior. We describe how Open vSwitch can be used to tackle problems such as isolation in joint-tenant environments, mobility across subnets, and distributing configuration and visibility across hosts.