VLANs and Inter-VLAN Communication

Question 1

What does VLAN stand for?

Answer 1

Virtual Local Area Network

Question 2

What is VLAN?

Answer 2

VLAN is a virtual local network where computers, servers, and other computer networks are logically connected regardless the physical area.

Question 3

What does VLAN provide?

Answer 3

• Improved Security
• Traffic Management
• Make a network simpler(by segmentation following groups)

Question 4

How does VLAN improve network performance? Explain

Answer 4

By separating large broadcast domains into smaller ones. (Since when there is only one broadcast domain, it would cause traffic since there are many hosts. With VLAN, it can separate them into respective groups, meaning smaller broadcast domains. )

Question 5

List the primary benefits of VLAN.

Answer 5

• Security
• Cost Reduction
• Better Performance
• Shrinks broadcast address
• Improved IT staff efficiency
• Simpler project and application management.

Question 6

Explain how Security is one of the benefits

Answer 6

Groups that have sensitive data can be separated from the rest of the network, decreasing the chances of the data being leaked

Question 7

Explain how it gives Cost Reduction

Answer 7

Since they are using vlan, they do not have to waste money on unnecessary expensive network upgrades and also the vlan is efficient in existing bandwidth and uplinks

Question 8

Explain how it gives Better Performance

Answer 8

Since VLANs can divide networks into multiple broadcast domains, it reduces the unnecessary traffic, hence it’ll boost performance.

Question 9

Explain how Shrinking Broadcast Address is one of the benefits

Answer 9

Dividing a network into VLANs would reduce the number of hosts of each broadcast domain.

Question 10

List the types of VLAN

Answer 10

-Data VLAN
-Default VLAN
-Native VLAN
-Management VLAN
Voice VLAN

Question 11

What is data VLAN configured to?

Answer 11

Data VLAN is configured to carry user-generated traffic (eg- VLAN 20, VLAN 10)

Question 12

Why are data VLANs sometimes referred to as user-VLANs?

Answer 12

They are referred to as USER VLANS because they divide networks into groups of users and devices. (Eg: VLAN 20 is only for STAFFS, VLAN 10 Is only for students.)

Question 13

Example of Default VLAN

Answer 13

VLAN 1

Question 14

Can default VLAN be renamed or deleted?

Answer 14

No

Question 15

What is tagged traffic

Answer 15

Tagged traffic are frames that are attached with VLAN information, with the information the main switch would know which VLAN the frame would want to go.

Question 16

What is native vlan?

Answer 16

Native vlan is is the VLAN that handles untagged frames. Untagged frames are assumed to not have a specific VLAN to go to, hence they would deliver the frame to every single VLAN in the network. So basically the frame is attached with a “native VLAN”, so when the main switch reads that, it’ll automatically send it to every switch. Example NATIVE VLAN IS VLAN 1 since VLAN 1 does not do tagging to the frames it sends, thus every VLAN will receive the frame.

Question 17

What is a trunk port?

Answer 17

Trunk ports are the links between switches that carry more than one VLAN.

Question 18

What is Management VLAN?

Answer 18

Management VLAN is a data VLAN that is configured for network management traffic.

Question 19

What is network management traffic?

Answer 19

Configuring another device with another device

Question 20

What is the type of network that has the transmission priority?

Answer 20

Voice over IP.

Question 21

What is voice VLAN?

Answer 21

Voice VLAN is a separate VLAN that supports VOICE over Ip traffic. They have assured bandwidth to ensure voice quality.

Question 22

explain the process on how the switches attach the vlan to the frame so that the frame can be tagged

Answer 22

When a pc that is connected to a vlan, we know that the vlan is connected to a configured port(switchport access vlan 10 is assigned to f0/11 port, meaning the pc is now connected to vlan 10 instead of the main switch). So when the switch receives a frame from the PC on that particular VLAN, it will attach the frame with the VLAN, so now the frame is tagged and the frame will be sent out to the trunk port.

Question 23

Why do we use trunk ports?

Answer 23

We use trunk ports to allow devices with different switches but same VLAN to communicate with each other. Trunks will basically open up all the VLANs, so for the case of different VLANs with diff networks, with routers they can now ping each other as the trunk opens up all the VLANs.

Question 24

How many byte and bits does a tag holds?

Answer 24

4 bytes, 32 bits

Question 25

what does a tag represent

Answer 25

Tags represent a VLAN

Question 26

What happens if a native VLAN receives a tagged frame and the frame is tagged as the same VLAN id as the native VLAN

Answer 26

It will drop the frame. Native vlan only receives untagged traffic.

Question 27

VTP stands for

Answer 27

VLAN trunking protocol

Question 28

What does VTP DO

Answer 28

Helps manage VLAN configurations between switches

Question 29

What can VTP store and learn?

Answer 29

VTP can only learn and store Normal Range Vlans.

Question 30

In normal ranged VLANs, where are their configurations stored?

Answer 30

Stored in a VLAN database file called vlan.dat, it is located in the switch’s flash memory.

Question 31

Where are the extended VLANs configurations stored at?

Answer 31

Running configurations.

Question 32

As we know that trunks would open VLANs, do they open all the VLANs available in the switch? (VLAN 1-4094)

Answer 32

NO! the trunk will only open the VLANs that were opened in that switch.