What is a VPN?
A VPN or Virtual Private Network is an encrypted connection over the Internet between two communicating end-points. In simple terms, it connects a computer to another computer (a server) somewhere on the Internet, allowing the connecting computer to communicate (such as browsing) securely. The encryption helps ensure that sensitive data is securely transmitted over an unsecured channel, that is the Internet. It prevents unauthorized parties from eavesdropping and making unauthorized modifications on the traffic communicated.
VPNs also serve to hide the IP address of a computer by replacing it with the address of the connected computer that could be located even in another country. In this sense, VPNs not only ensure confidentiality and integrity of a communication, they also protect the privacy by hiding the source IP of each packet transmitted over the Internet.
This technology is widely used in corporate environments to enable the employees to connect to the corporate servers securely or to secure traffic exchanged between servers located at different corporate sites. Though VPNs were originally created for this corporate use case, they are also popular nowadays for personal use, such as to secure browsing activity from prying eyes on a public Wi-Fi.
How Does a VPN Work?
When a computer (such as a laptop, tablet or smartphone) is connected to a remote server over VPN (Remote Access VPN), the computer acts as if it is on the same local network as the connected server (thus the name Virtual Private Network). After establishing a VPN connection, all the network traffic of the connecting computer is sent over a secure connection to the remote server.
To state it differently, a computer connected to a remote server over VPN, can use the Internet as if it were present at the remote server’s location (local network). Thus the connecting computer can take advantage of the security benefits provided by the connected local network.
Are There Any Downsides to Using a VPN?
For the downside, the benefit of confidentiality, integrity and privacy on a VPN connection does not come free. The underlying mechanism of encryption that provides these features could also add a bit of load on the computer processor, resulting in a little bit slow down on the connection. However, thanks to the improvements in both computers and VPN technology, this negative impact is almost unnoticeable today.
Types of VPNs
- Remote Access VPN (Corporate Use): VPN technology was originally developed to allow remote workers access to corporate resources. A remote access VPN connects a device outside the corporate network, such as laptops, tablets or smartphones (end-points), to corporate resources (servers) securely. Usually, before connecting to the corporate servers, a security check is conducted on the end-points to make sure they meet a certain security posture in order not to compromise the security of the connection to be established.
- Remote Access VPN (VPN Service Provider): Today, however, VPN is mostly used by individuals to surf privately and securely on the Internet. For this purpose, a VPN service provider can be used to transmit the original traffic over the service provider’s servers. Through such a connection, source IP address of any traffic originating from the connecting computer shall replaced with the IP address of the connected service provider’s server. This is basically how privacy is achieved through a VPN connection in addition to having an encrypted traffic.
- Site-to-Site VPN: A site-to-site VPN helps connect two geographically separate corporate offices by establishing a secure channel between servers located at each sites. For this purpose, usually dedicated equipment is used to establish and maintain a connection.

Only people with dull lives can afford to forego privacy.
Jan Chipchase
Read more educational and inspirational cyber quotes at our page 100+ Best Cyber Security & Hacker Quotes.
Use Case Scenarios for VPNs
- Tunneling Between Two Corporate Sites: Traffic between two different corporate locations can be connected through VPNs in tunnel mode.
- Accessing a Corporate Network from a Remote Location: Employees can connect to corporate resources through VPNs in remote access mode while working from home or while traveling.
- Accessing a Home Network from a Remote Location: Similar to accessing to the corporate network, it is possible to set up a VPN connection to a home network while traveling.
- Hiding Your Activity from Your Local Network or ISP: Your traffic is visible to the Internet Service Providers (ISPs) or to the eavesdroppers on a network (local network or Internet) if it is not encrypted. For instance, web browsing activity can be seen by anyone on a local network (as in the case of using a public Wi-Fi connection) when connecting to non-HTTPS websites. In such cases, VPNs can help individuals hide their traffic from preying eyes.
- Access Region Restricted Services: VPNs can help to access the same services offered at your home location when traveling. It could also be the case that you would like to access a service or content offered at a different location than your home location. This is possible via a VPN service, because a computer connected to a remote server over VPN, can use the Internet as if it were present at the remote server’s location.
- Bypass Internet Censorship: VPNs can also be used to get around the restrictions or censorships imposed on your local area network or ISP (restrictions by governments).
- Prevent Price Discrimination: Price discrimination is offering different prices to different people based on their perceived ability to pay and this discrimination is usually made according to the location of the customers. A user can check if they are subject to a price discrimination by reconnecting to the same site, but this time using a VPN connection.
- Bypass Download Restrictions from Certain Sources: Similar to the above use case, ISPs or local network administrators can prevent users from downloading from certain sites or deny using certain applications/protocols like BitTorrent. Or, they can throttle your download speed when using certain application/protocols. Such restrictions and regulations can be bypassed by using VPNs.
- Bypass Download Count Restrictions: Last but not least, some sites may limit downloads per user based on download counts. Such sites usually check the IP addresses of the users to track the download counts. It is possible to get around this limitation by establishing a VPN connection after reaching a download limit. Since the new connection will have the source IP of the VPN server rather than the connecting computer itself, the user’s download limit shall reset instantly.
Given many benefits of using a VPN service, if you decide to use a VPN product but don’t know which one to choose from among the alternatives, you can read our articles Best VPN Services or Best Free VPN Services to help you decide on a suitable VPN product according to your needs.