The Virtual Switching is a technology allowing multiple switching functions to happen in one physical device or single functional switching to happen in multiple physical devices across network, while in the situation of a real switch, switching is conducted in one physical switch. Virtual switching technology enables a single switch to be used for many different applications. Each different function may have its own discrete performance and security controls. Using virtual switching technology, Service providers can create a dynamic service mix, as desired, without requiring new hardware and enabling the gradual evolution to include new services or a common control plane. Virtual switching is a core concept in the Multiservice network switching architecture.

Multiservice Switching Forum (MSF) defined an architectural framework for a multiplane system to provide Virtual Switching functions, which provides a high degree of flexibility, simultaneously supporting Asynchronous Transfer Mode (ATM), voice, and Internet Protocol (IP) services, with separate control planes for maximum service efficiency.

The multiplane architectural framework consists of five logical Planes: Adaptation, Switching, Control, Applications and Management. The Adaptation Plane supports the physical interface to a user or another network element. The Switching plane supports the actual switching fabric by which physical interfaces are connected. The Control Plane provides the capability to manage network service events and provides control over both the Adaptation and Switching Planes. The Application and Management Planes provide services that use the capabilities of the Control plane.

The MSF framework is designed to allow multiple controllers to share the resources of the Switching Plane and the Adaptation Plane. Using service and policy management to switch resources, the controllers can be separate or combined to support the network applications. In effect, virtual switches are created by each controller. This enables multiple, simultaneous Control Planes to direct the Forwarding Plane, along with highly granular control of multiple Control Planes on a single port. Service providers using the Virtual Switch Architecture can support ATM, voice, and IP services simultaneously, with separate control planes for maximum service efficiency. They can provision separate queues for delivering ATM and IP QoS natively, allowing for simultaneous use of ATM CoSs and IP QoS.

Virtual Switching

Related Terms: Multiservice switch, QoS, ATM, IP, VoIP

Reference Links: http://www.msforum.org/techinfo/approved.shtml: Multiservice switching architecture and technologies