VLAN vs Subnet: What Are Differences?
VLAN and Subnet are both developed to deal with segmenting or partitioning a portion of the network. And they also share such similarities as restricting broadcast domains or ensuring security through isolation of different sub-networks. However, there are obvious differences between them on operation, functionality and deeper objectives.
For enthusiasts new to IP Networking terminology, VLAN and IP Subnet terms may look confusing. Many times in technical discussions things like Inter VLAN communication, interchangeably using terms like VLAN A / VLAN B or Subnet A/Subnet B are used. This further adds salt to the wound.
So, let’s have brief on terminologies of VLAN and IP Subnet and before discussing the difference (vlan vs subnet) from each other.
VLAN :
VLAN stands for Virtual Local Area networks and they are defined by 802.1q protocol (it’s a VLAN tagging protocol that allows the ethernet frame size to increase by four bytes due to the insertion of a four-byte VLAN tag into the ethernet frame). Using VLANs we can virtually separate our LANs into smaller networks, they work like normal LANs except they are logically or virtually separated as opposed to physically.
There are a few reasons to use VLANs, one of the main reasons is to broadcast traffic. VLANs give us all of the benefits of physically separating our network virtually without spending extra money on hardware. The traffic still behaves in the same way as if it was physically separated or split.
Benefits of VLAN
VLANs make it easier to split a single switched network to match the security and functional requirements of the system without making any drastic changes in the network infrastructure.
With VLANs, we can set up Multiple Virtual networks on one physical port and on Wi-Fi.
They are also important because they help in improving the overall performance of a network by grouping the most frequently communicating devices together.
VLAN reduces the broadcast traffic and also makes it very easy to control broadcast domains.
It makes Network administration easy.
Increases security.
Subnet :
Subnet/subnetwork is a network inside a network or it’s a smaller section (subnetwork) of a large network. Basically, subnets are a logical partition of an IP network into several smaller networks for making the network fast and efficient.
Benefits of Subnets
Subnetting divides broadcast domain i.e., improves the speed, efficiency, and network performance.
Reallocating IP addresses
Reduce network congestion
Improve network security
VLAN vs Subnet: What’s the Difference?
As mentioned above, VLAN and Subnet are totally different things in a close look. The following chart lists the differences between VLAN and Subnet in details:
| Parameter | VLAN | Subnet |
| Definition | VLAN is a logical LAN that contains broadcasts within itself, and only hosts belonged to that VLAN will see those broadcasts. | Subnet is an IP address range of IP addresses that help hosts communicate over layer 3. |
| Logical and Physical Network | VLAN allows us to create different logical and physical networks. | Subnet allows us to create logical networks through the same physical network. |
| Network Member Control | A VLAN is configured at server/router side. The one who controls the router/server decides which computer/port is assigned to which VLAN. For example, if you have a 24 port 10GbE switch, you can assign 12 ports to VLAN 1 and the others to VLAN 2. | A Subnet is determined by the IP you use and the IP can be chosen by the admin of a computer (or device). Therefore it is done on the client side – you can not control it. |
| OSI Layer | VLAN is a layer 2 term where MAC addresses work. | Subnet is a layer 3 term where IP layer works. |
| Hardware/Software Based | More of software-based terminology. | More of hardware-based terminology. |
| Security & Control | VLANs perceived to be more secure and provide more robust control for the network. | Subnet has limited control in comparison to VLAN. |
| Major Benefit | VLAN is extremely flexible, it brings better work performance, less traffic, and more efficiency. | A Subnet will not be affected when other Subnets going down or having technical breakdowns. |
VLAN vs Subnet: Which to Choose?
VLAN and Subnet both have their advantages and limits. For example, VLAN allows for the creation of different logical and physical networks while Subnet only allows for the creation of different logical networks. However, if a network sniffer is employed, users from one Subnet can discover the existence of other Subnets, this will not happen to users of different VLANs.
