Home Computer What is a Virtual Private Network (VPN)? How it works

What is a Virtual Private Network (VPN)? How it works


Virtual Private Networks (VPNs) allow the provision of private network services to an organization or organizations on a shared infrastructure. VPN Backbone is a shared service provider backbone network. It is used to transport traffic for multiple VPNs, as well as possibly non-VPN traffic.

Over the last few years, IP and IP / Multi-Protocol Label Switching (MPLS) based VPNs have become increasingly popular. However, VPNs provided using technologies such as frame relay and asynchronous transfer mode (ATM) virtual circuit (VC) have long been available.

WAN – Limitations

Until yesterday, reliable communication meant the use of leased lines to maintain a wide area network. Leased lines from Integrated Services Digital Services to Optical Carrier 3 Fiber provide the company with a way to expand their private network beyond their immediate physical area. When it comes to security, performance, reliability, WAN has obvious advantages over public networks. However, maintaining a WAN is expensive.


As the net popularity grows, businesses have resorted to expanding their own networks. It started with intranets, then VPN. The latter was to connect distant employees with the office.

VPN defined

A typical VPN can have a main LAN at the company’s corporate headquarters, remote facilities or other LANs in the office and individuals connecting from outside the field.

Also, a VPN is a private network that uses a public network to link to remote sites or users. Instead of using a dedicated, real-world connection, for example, a leased line VPN uses a remote employee from the company’s private network or a ‘virtual’ connection routed to the site via the Internet.

Types of VPNs

We have two types of VPN –

Remote access – Also known as a virtual dial-up network, this is a user-to-LAN connection used by the company with employees who need to connect to a private network from a remote location. Typically, a corporation wishing to set up a large remote access VPN provides its users with some type of Internet dial-up account using an Internet service provider. Then, telecommuters can dial 1-800 to access the Internet using their VPN client software to access the corporate network. An excellent example of a company that needs a VPN for a company with countless field salespeople. Remote-access VPNs allow remote users through encrypted, secure connections between the company’s own networks and third-party service providers.

Site to site – Using dedicated tools and large-scale encryption, the company can connect multiple fixed sites on the public network. Each site requires only a local connection with the same public network. Thus they save money on a long private lease line. The site for VPN can, in turn, be grouped into extranets or intranets. When a VPN is created to connect a company with its partner or customer, it is called Extranet VPN. A site-to-site VPN built between the offices of the same company is called an intranet VPN.

A well-designed way can have a positive impact on a company

  • Regional connectivity areas;
  • Reduction in operating costs;
  • Reduction of transport time;
  • Increase productivity;
  • Simplify network topology;
  • Provide opportunities for global networking;
  • Provide telecommunication support;
  • More ROI than WAN.

Features of a well-designed VPN network

  • Security;
  • Reliability;
  • Scalability;
  • Policy management;
  • Network management.

VPN technologies

Above all, VPN uses a variety of methods to secure connections and data

  • Data Privacy – Because your private data travels over the public network, data encryption ensures data privacy.
  • Data Integrity – It is important to check whether the data has changed during transit.