Abstract: The Virtual Networks that are private from every other customer/Client/ Site to Site has Virtual Private Network (VPN) that’s a reason the VPN refers to the Layer 3 VPNs. MPLS enabled application like Layer 3 VPN. MPLS Application is not about IPsec and cryptography but a VPN with Layer 3 VPN & MPLS Services. Virtually it’s all about separating a set of network from another set of network. It’s separated from each of the customer’s network which is a private domain, for e.g. MIT ADT and JSPM are two different customers for a services provider, in which MIT-ADT is private network from JSPM’s network. Mostly it has been used by service provider in the past, but it has become a trend for the big and even small organizations to go for MPLS L3 VPN. As it is a cost effective, well known for speed, Label switching at Layer 2.5, and good for security