What is an SVI?

A Switched Virtual Interface (SVI) is crucial in multilayer switches as it serves as a virtual interface that enables communication between VLANs. SVIs function as Layer 3 interfaces associated with a specific VLAN, allowing the switch to perform routing functions for that VLAN. When a device needs to send data to another device on a different VLAN, the SVI for the originating VLAN approaches the routing process and direct the traffic efficiently.

This capability also allows for features such as inter-VLAN routing, which enhances network efficiency and management. With SVIs, a switch becomes more than just a Layer 2 device; it can also route packets between VLANs, reducing the need for external routers in many scenarios, thus streamlining network design.

The other options do not accurately represent an SVI's function: static routing protocols refer to methods of routing packets in a network, physical interfaces are tangible ports on a switch, and network protocols for VLANs describe how VLANs operate but do not define the specific virtual interface used for Layer 3 communication.