Types of VLAN

There are different types of VLANs. The type of network traffic they carry defines a particular type of VLAN and others derive their

names due to the type or a specific function the VLAN performs. The following describes common VLAN:

Default VLAN

At the initial boot up of the switch, All switch ports become a member of the default VLAN, which makes them all part of the same broadcast domain. This allows any network device connected to any of the switch port to communicate with other devices on other switch ports.

On Cisco switches the default VLAN is VLAN 1. VLAN 1 has all the features of any VLAN, except that you cannot rename or delete it.

Data VLAN

A data VLAN that can also be referred to as user VLAN. This is configured to carry only user-generated traffic. The importance of separating user data from other type of VLAN is proper switch management and control.

Native VLAN

A native VLAN is assigned to an 802.1Q trunk port. An 802.1Q trunk port supports traffic coming from many VLANs as well as traffic that do not come from a VLAN. The 802.1Q trunk port places untagged traffic (traffic that does not come from a VLAN) on the native VLAN. In summary, the native VLAN observes and identifies traffic coming from each end of a trunk link.

Management VLAN

A management VLAN is any VLAN you configure to access the management capabilities of a switch. Your configured management VLAN is to be assign with an IP address and subnet mask. Any of a switch VLAN could be configured as the management VLAN if you has not configured or define a unique VLAN to serve as the management VLAN. In some cases, a network administrator proactively defines VLAN 1 as the management VLAN; this enables a loophole for an unauthorized connection to a switch.

Voice VLAN

Voice VLAN is configured to carry voice traffic. Voice VLANs are mostly given transmission priority over other types of network traffic. Communication over the network is not complete without phone calls. More calls are made over the network than other forms of s message transmission. Sending emails and text messages are also forms of inter-relations but listening to a real voice provides legitimacy and assurance.

It is considered among network administrators to design a network that support VoIP with an assured bandwidth to ensure voice quality, and capability to be routed around congested areas on the network with minimal delays (150-180 milliseconds).

In next post we will see each VLAN in practicals.