VLAN vs. VXLAN

Attribute	VLAN	VXLAN
Layer	Layer 2	Layer 2
Number of IDs	4096	16 million
Encapsulation	802.1Q	UDP
Header Size	4 bytes	50 bytes
Scalability	Limited	Highly scalable

Introduction

Virtual Local Area Network (VLAN) and Virtual Extensible LAN (VXLAN) are both technologies used in networking to segment and isolate traffic within a network. While VLAN has been around for a longer time and is widely used, VXLAN is a newer technology that offers some advantages over traditional VLAN. In this article, we will compare the attributes of VLAN and VXLAN to help you understand the differences between the two.

Definition

VLAN is a method of creating multiple broadcast domains within a single physical network. It allows network administrators to segment traffic based on logical groupings, regardless of the physical location of the devices. VLAN tags packets with a VLAN ID, which is used to determine which devices can communicate with each other. On the other hand, VXLAN is a technology that extends VLANs across different data centers or cloud environments. It encapsulates Layer 2 Ethernet frames within Layer 3 UDP packets, allowing for greater scalability and flexibility in network design.

Scalability

One of the key differences between VLAN and VXLAN is scalability. VLANs are limited to 4096 VLAN IDs, which can be a constraint in large networks with many devices. VXLAN, on the other hand, can support up to 16 million VXLAN IDs, making it much more scalable for modern network environments. This scalability is achieved through the use of a 24-bit VXLAN Network Identifier (VNI) field, which allows for a much larger number of unique identifiers compared to VLAN.

Isolation

Both VLAN and VXLAN provide isolation of traffic within a network, but they do so in different ways. VLAN isolates traffic at Layer 2 by creating separate broadcast domains, while VXLAN isolates traffic at Layer 3 by encapsulating Ethernet frames within UDP packets. This means that VXLAN can provide isolation across different IP subnets, making it more flexible for use in multi-tenant environments or cloud deployments where devices may be located in different networks.

Overhead

Another important consideration when comparing VLAN and VXLAN is the overhead associated with each technology. VLAN adds a 4-byte VLAN tag to each Ethernet frame, which can increase the size of packets and consume additional bandwidth. VXLAN, on the other hand, adds a 50-byte VXLAN header to each packet, which includes the VNI and other information needed for encapsulation. While this overhead is larger than VLAN, it is necessary for the additional features and flexibility that VXLAN provides.

Interoperability

When it comes to interoperability, VLAN has the advantage of being a widely adopted standard that is supported by most networking equipment. This makes it easy to implement VLANs in existing networks without the need for specialized hardware or software. VXLAN, on the other hand, is a newer technology that may require specific hardware or software support to implement. However, VXLAN is gaining popularity in modern network designs and is supported by many vendors, making it a viable option for organizations looking to take advantage of its benefits.

Conclusion

In conclusion, VLAN and VXLAN are both valuable technologies for segmenting and isolating traffic within a network. While VLAN is a well-established technology with widespread support, VXLAN offers greater scalability and flexibility for modern network environments. When choosing between VLAN and VXLAN, it is important to consider factors such as scalability, isolation, overhead, and interoperability to determine which technology best meets the needs of your network. Ultimately, both VLAN and VXLAN have their own strengths and weaknesses, and the choice between the two will depend on the specific requirements of your network environment.