5.6

Question 1

What’s the purpose of VLANs?

Answer 1

To reduce load on a router by dividing traffic on the broadcast domain

Question 2

How is info about VLANs communicated from switches and routers?

Question 3

How do voice VLANs help VoIP work effectively?

Question 4

How does routing between VLANs work?

Question 5

What command reports VLAN ID’s on a switch?

Answer 5

“show vlan”

Question 6

What command deletes a VLAN?

Answer 6

“no vlan”

Question 7

What is “Trunking”?

Answer 7

Interconnecting switches to build redundancy

Question 8

What does IEEE 802.1Q do for Trunking?

Answer 8

Assign VLAN ID’s (VIDs) so packets know where to travel when trunking.

Question 9

What ID is the default VLAN?
Can this be changed?

Answer 9

1
No

Question 10

How should default VLAD be used?

Answer 10

Remain unused or ONLY for inter-switch protocol traffic like STP.

Question 11

What is a native VLAN?

Answer 11

Untagged traffic is put when getting frames over a trunk port.

Typically gotten from legacy devices

Question 12

What is Voice or Auxiliary VLAN?

Answer 12

Auto configures VoIP to prevent manual complexity

Question 13

What are 2 ways to manage VLAN?

Answer 13

Subinterfaces and Switch Virtual Interfaces

Question 14

What is subinterfaces for VLAN routing?

Answer 14

Assign trunk on a router to multiple “subinterfaces” on the router. Each “subinterface” is for a different VLAN.

This is called “Router on a Stick”
1 Port handles traffic for many VLANS (subinterfaces)

Question 15

How do you configure a subinterface?

Answer 15

interface G0.16 (Create subinterface)

encapsulation dot1Q 16 (Subinterface to VLAN 16)

ip address 198.51.100.30 255.255.255.240 (Subinterface’s ID)

Question 16

What is a Switch Virtual Interface?

What problem does it solve?

Answer 16

Subinterfacing is inefficient for scaling.

Switch Virtual Interface means each VLAN gets it’s own Router spreading the load (compared to “Trunking” in Subinterface)