What is VLAN and how does it function?
A VLAN (Virtual Local Area Network) is a way to segment a physical network into logical subgroups. This allows for greater network organization and security, as well as the ability to segment network traffic.
What is the difference between a VLAN and a subnet?
A VLAN segments a physical network into logical subgroups, while a subnet segments a larger IP address space into smaller subgroups.
How does VLAN tagging work?
VLAN tagging is a method of identifying packets as belonging to a specific VLAN. This is done by adding a VLAN tag, or header, to the packet, which includes information such as the VLAN ID and priority.
VLAN tagging allows for the segregation of different types of traffic, such as voice and data, on the same physical network.
How do you configure a VLAN on a switch?
The process for configuring a VLAN on a switch will vary depending on the specific switch and its operating system. However, the general steps include:
Logging into the switch and entering configuration mode
Creating a VLAN by assigning it a unique ID and a name
Assigning switch ports to the VLAN
Configuring any necessary VLAN tagging or trunking
Saving the configuration changes
Why we create VLANs?
Broadcast control
Performance
Security
Department-wise segmentation
How to delete a VLAN?
VLAN information is not saved in the running config or startup config of the switch. It is saved in VLAN.dat in Flash memory.
Difference between Trunk and Access Port?
Access Port: Carries traffic of a single VLAN.
Trunk Port: Carries traffic of multiple VLANs. By default, all VLANs are allowed on a trunk.
What is Inter-VLAN Routing?
When a host from one VLAN wants to communicate with a host in another VLAN, the traffic must be routed between them. This process is called Inter-VLAN Routing.
Difference between ISL and IEEE 802.1Q?
ISL: Cisco proprietary. The original frame is encapsulated with a 26-byte header and a 4-byte FCS.
802.1Q: Industry standard. Uses only a 4-byte tag.
VLAN Range?
VLAN range: 0 - 4096
Default VLAN: 1
Normal VLAN range: 2 - 1001
Reserved for token ring: 1002 - 1005
Extended VLAN: 1006 - 4095