Native VLAN vs. Tagged VLAN

Attribute	Native VLAN	Tagged VLAN
Definition	The VLAN that is untagged on a trunk port	The VLAN that is tagged on a trunk port
Default VLAN	VLAN 1	None
Security	Less secure as it is untagged	More secure as it is tagged
Interoperability	Compatible with devices that do not support VLAN tagging	Requires devices to support VLAN tagging

Introduction

When it comes to setting up VLANs in a network, two common types that are often used are Native VLAN and Tagged VLAN. Both serve different purposes and have their own set of attributes that make them unique. In this article, we will compare the attributes of Native VLAN and Tagged VLAN to help you understand the differences between the two.

Native VLAN

Native VLAN is a term used in networking to refer to the VLAN that is not tagged with a VLAN ID. In other words, it is the default VLAN that is used for untagged traffic on a trunk port. When a frame enters a trunk port without a VLAN tag, it is placed in the Native VLAN. This VLAN is typically used for management traffic or for devices that do not support VLAN tagging.

One of the key attributes of Native VLAN is that it is untagged, which means that the frames belonging to this VLAN do not have a VLAN ID attached to them. This can make it easier to configure and manage, especially for devices that do not support VLAN tagging. Additionally, Native VLAN can help prevent VLAN hopping attacks, as it separates untagged traffic from tagged traffic on a trunk port.

Another attribute of Native VLAN is that it can be configured on a per-port basis, allowing network administrators to specify which VLAN should be considered as the Native VLAN for each trunk port. This flexibility can be useful in scenarios where different VLANs are used for different purposes, such as separating voice and data traffic.

Native VLAN can also be used to carry untagged traffic between switches in a network. This can be useful in scenarios where devices do not support VLAN tagging or when there is a need to pass untagged traffic between switches without losing VLAN information.

In summary, Native VLAN is a default VLAN used for untagged traffic on a trunk port. It is untagged, can be configured on a per-port basis, and can be used to carry untagged traffic between switches.

Tagged VLAN

Tagged VLAN, on the other hand, is a VLAN that is assigned a VLAN ID and is used to carry traffic from multiple VLANs over a single trunk port. When a frame enters a trunk port with a VLAN tag, it is placed in the corresponding VLAN based on the VLAN ID. Tagged VLANs are commonly used in environments where multiple VLANs need to be supported on a single trunk link.

One of the key attributes of Tagged VLAN is that it allows for the segregation of traffic from different VLANs on the same physical network. By assigning a VLAN ID to each frame, network administrators can ensure that traffic from one VLAN does not interfere with traffic from another VLAN, even when they are transmitted over the same trunk link.

Tagged VLAN also provides flexibility in network design, as it allows for the creation of multiple logical networks within a single physical network infrastructure. This can be useful in scenarios where different departments or user groups need to be isolated from each other for security or performance reasons.

Another attribute of Tagged VLAN is that it requires support for VLAN tagging on both ends of the trunk link. This means that devices connected to the trunk port must be capable of adding and interpreting VLAN tags in order to correctly process traffic from different VLANs. While this adds complexity to the network configuration, it also provides greater control over traffic flow and security.

In summary, Tagged VLAN is a VLAN that is assigned a VLAN ID and is used to carry traffic from multiple VLANs over a single trunk port. It allows for the segregation of traffic from different VLANs, provides flexibility in network design, and requires support for VLAN tagging on both ends of the trunk link.

Comparison

Now that we have discussed the attributes of Native VLAN and Tagged VLAN, let's compare the two types of VLANs based on their key characteristics:

• Tagging: Native VLAN is untagged, while Tagged VLAN is assigned a VLAN ID and requires support for VLAN tagging on both ends of the trunk link.
• Default VLAN: Native VLAN is the default VLAN used for untagged traffic on a trunk port, while Tagged VLAN is used to carry traffic from multiple VLANs over a single trunk port.
• Flexibility: Native VLAN can be configured on a per-port basis, providing flexibility in network design, while Tagged VLAN allows for the creation of multiple logical networks within a single physical network infrastructure.
• Security: Native VLAN can help prevent VLAN hopping attacks by separating untagged traffic from tagged traffic, while Tagged VLAN allows for the segregation of traffic from different VLANs on the same physical network.
• Complexity: Native VLAN is simpler to configure and manage, especially for devices that do not support VLAN tagging, while Tagged VLAN adds complexity to the network configuration but provides greater control over traffic flow and security.

Conclusion

In conclusion, Native VLAN and Tagged VLAN are two common types of VLANs that serve different purposes in a network. Native VLAN is used for untagged traffic on a trunk port and is simpler to configure and manage, while Tagged VLAN is used to carry traffic from multiple VLANs over a single trunk port and provides greater control over traffic flow and security. Understanding the attributes of Native VLAN and Tagged VLAN can help network administrators make informed decisions when setting up VLANs in their network infrastructure.