VLAN vs Subnet
Subnetting and implementation of VLANs provide administrators flexibility when trying to come up with networks on medium to very large scales. In essence, VLANs and subnets are similar in the purpose of their development. But when you peel off their general similarities, obvious differences emerge whether by functionality, operation, or deeper objectives.
VLAN (Virtual Local Area Network) exists when two or more ports are connected physically or grouped together by some piece of network hardware/software that supports VLAN functionalities. On the whole, a VLAN is very similar to that of a physical LAN. Their main difference is VLANs capability to group end stations together without the requirement of being located on the same network switch. In VLAN, configuration of the network can be done via software extensively. Basically, VLANs are used at layer 2 to break up broadcast domains.
Each VLAN is considered as a separate entity and it can only reach another VLAN through a router. You can use a single network with VLANs but when one network goes down for some reason, the entire logical network is concerned. VLANs are very useful when an IT professional (system or network admin) wants to group organization departments for better work performance, less traffic, and more efficiency.
A subnet is essentially a group of IP addresses. Any particular address can reach any address without using any routing device if they belong to the same subnet. Now, if the address you want to reach is outside of your subnet, then just like in VLANs, you will have to go through a router. Subnet is at layer 3 (IP), wherein IP addresses belong.
When you are subnetting, you are actually dividing an IP address into smaller subnets. This accomplishes an addition of multiple networks to the system, a thing that any organization or agency would constantly need. The great thing about subnetting is that subnets are unaffected with other subnets going down or having technical breakdowns.
It can be said that VLAN is software-based and subnetting is primarily hardware-based. Though VLANS are somewhat perceived to be lacking in security as they can be hacked, it is still the more popular network segregation of choice by many administrators.
Summary:
1. VLAN is found to be more popular than subnetting but, more often than not, both are used to complement each other.
2. VLAN is works at the layer 2 while subnet is at layer 3.
3. Subnets are more concerned about IP addresses.
4. Many would consider that subnetting is more secure but VLAN brings more network efficiency.
5. VLAN is largely software-based while subnet is hardware-based.