200-301 Question 222

Community Discussion

Written by other learners. Comments can disagree with the marked answer — check the official documentation when in doubt.

• Chose ABE1

  A new switch has no VLANs configured: Cisco's documentation states that new switches typically have VLAN 1 configured by default but do not have user-defined VLANs until configured. Cisco VLAN Configuration Guide Connectivity between VLANs requires a Layer 3 device: VLANs are isolated broadcast domains, and inter-VLAN routing requires a Layer 3 device (router or Layer 3 switch). Cisco Inter-VLAN Routing A switch maintains a separate bridging table for each VLAN: Each VLAN on a switch has its own MAC address table, allowing it to manage traffic independently within each VLAN. Cisco VLANs and Switching

• 1

  D is ambiguous. What does 'separate address space mean? If it means each VLAN's address space is independant and irrelevant to other VLANs, that's correct. Actually you can use the same IP range from multiple VLANs. But if it means the IP address ranges have to be separate, not overlapping or identical, then it's wrong. VLAN is a layer2 thing. VLAN itself does not care about IP addresses. We use different IP ranges for different VLAN purely for management convenience.

• 1

  We usually chose different IP ranges for differen VLANs, because (1) we want to differenciate networks for management purpose; (2) we want them be routable to each other; (3) when we connect them to each other through a router, the subinterfaces must have different IP ranges. However, this question has not given any application scenario or context; it's purely a question at the theory level. So, according to the definition and principle of the term 'VLAN', different VLANs definitely can contain identical or overlapping IP ranges. They are parallel universes.