Explanation: A Switched Virtual Interface (SVI) is a virtual interface on a Cisco switch that represents a VLAN. SVIs play a critical role in modern network design by allowing inter-VLAN routing and management through a logical interface rather than relying on physical ports. Understanding the properties and capabilities of SVIs is essential for configuring and managing multilayer switches. A. Virtual Interface for Routing: SVIs are created to provide Layer 3 connectivity to a VLAN. They enable the switch to perform routing between VLANs (inter-VLAN routing) without the need for an external router. This capability is one of the key features of multilayer switches and helps streamline network design by consolidating routing functions within the switch itself. B. IP Address Assignment: An SVI can be configured with an IP address. This address serves two main purposes: it acts as the default gateway for devices in the associated VLAN and allows the switch to be managed remotely (e.g., via Telnet, SSH, or SNMP). The IP address on an SVI is essential for both routing and management functions. C. Multilayer Switch Requirement: SVIs are generally supported on multilayer (Layer 3) switches that are capable of routing. While traditional Layer 2 switches do not perform routing and therefore do not require SVIs for routing purposes, many modern switches incorporate both Layer 2 and Layer 3 capabilities. In these devices, SVIs are a fundamental component for inter-VLAN routing and advanced network features. D. SVI Creation: SVIs are not created automatically simply by creating a VLAN. Instead, an SVI must be explicitly configured by entering the appropriate interface configuration mode (e.g., “interface Vlan10”) and then assigning an IP address. The VLAN’s existence on the switch does not automatically result in the creation of a corresponding SVI. This means that Option D is incorrect. Use Cases and Benefits: Inter-VLAN Routing: SVIs allow devices in different VLANs to communicate with each other without the need for an external router. This improves performance and reduces latency. Management: By assigning an IP address to an SVI, the switch can be managed remotely. The SVI IP address typically serves as the default gateway for devices in the VLAN. Simplification: Using SVIs simplifies network design by consolidating routing capabilities within the switch. This reduces the need for additional hardware and streamlines configuration and troubleshooting. Conclusion: The correct statements about SVIs are that they are virtual interfaces used for inter-VLAN routing (Option A), they can be assigned an IP address (Option B), and they are available on multilayer switches (Option C). The notion that SVIs are created automatically when a VLAN is configured is incorrect (Option D). Mastery of SVI concepts is crucial for network professionals involved in configuring and managing modern enterprise networks.