Networking - Virtual LANs

Exercise :: Virtual LANs - Virtual LANs

  • Virtual LANs - Virtual LANs

Which of the following provide inter-switch VLAN communication?

  1. ISL
  2. VTP
  3. 802.1Q
  4. 802.3Z

A. 2 only
B. 1 and 3
C. 2 and 4
D. 2, 3 and 4

Answer: Option B


ISL is a Cisco-proprietary frame-tagging method. IEEE 802.1Q is the nonproprietary version of frame tagging.


A switch has been configured for three different VLANs: VLAN2, VLAN3, and VLAN4. A router has been added to provide communication between the VLANs. What type of interface is necessary on the router if only one connection is to be made between the router and the switch?

A. 10Mbps Ethernet
B. 56Kbps Serial
C. 100Mbps Ethernet
D. 1Gbps Ethernet

Answer: Option C


Although you can use either 100Mbps or 1Gbps Ethernet, the 100Mbps is necessary at a minimum and is the best answer to this question. You need to trunk the link from the switch to the router to make this connection work with inter-VLAN communication.


Which of the following are benefits of VLANs?

  1. They increase the size of collision domains.
  2. They allow logical grouping of users by function.
  3. They can enhance network security.
  4. They increase the size of broadcast domains while decreasing the number of collision domains.
  5. They simplify switch administration.
  6. They increase the number of broadcast domains while decreasing the size of the broadcast domains.

A. 1 and 5
B. 2 and 4
C. 1, 3 and 5
D. 2, 3 and 6

Answer: Option D


VLANs break up broadcast domains in a switched layer 2 network, which means smaller broadcast domains. They allow configuration by logical function instead of physical location and can create some security if configured correctly.


Which of the following protocols are used to configure trunking on a switch?

  1. VLAN Trunk Protocol
  2. VLAN
  3. 802.1Q
  4. ISL

A. 1 only
B. 3 only
C. 3 and 4
D. 1, 3 and 4

Answer: Option C


Cisco has a proprietary trunking protocol called ISL. The IEEE version is 802.1Q.


What VTP mode allows you to change VLAN information on the switch?

A. Client
C. Server
D. Transparent

Answer: Option C


Only in server mode can you change VTP information on a switch.