A. A new switch has no VLANs configured.
B. Inter-VLANs communication requires a Layer 3 device.
C. VLANs typically decrease the number of collision domains.
D. Each VLAN is a different broadcast domain.
E. A switch has to identify the VLAN an address belongs to in the forwarding table.
F. VLANs cannot cross multiple switches.
Answer: B, D and E.
By default, all ports on a new switch belong to VLAN 1 (default & native VLAN). There are also some well-known VLANs (for example: VLAN 1002 for fddi-default; VLAN 1003 for token-ring…) configured by default. Answer A, a new switch has no VLANs configured, is not correct.
To communicate between two different VLANs (inter-VLAN) we need to use a Layer 3 device like router or Layer 3 switch. Answer B, inter-VLANs communication requires a Layer 3 device, is correct.
VLANs don’t affect the number of collision domains, that is based on the number of physical ports on the switch. Answer C, VLANs typically decrease the number of collision domains, is not correct.
Typically, VLANs increase the number of broadcast domains. We must use a different network (or sub-network) for each VLAN. Answer D, cach VLAN is a different broadcast domain, is correct.
A switches bridging table has been modified to include the VLAN number so that it can only send frames to devices on the same VLAN. For example, if a PC in VLAN 2 sends a frame then the switch look-ups its bridging table and only sends frame out to other devices which belong to VLAN 2 (it also sends this frame on trunk ports), Answer E, a switch has to identify the VLAN an address belongs to in the forwarding table, is correct.
We can use multiple switches to expand VLAN reach and port density. Answer F, VLANs cannot cross multiple switches, is not correct.
