Virtual Private Network (VPN) – Definition, Features,Types and Uses

What is Virtual Private Network (VPN)?

A virtual private network (Virtual Private Network, or VPN) is a technology that creates an encrypted connection through a less secure network. The advantage of using a secure VPN is that it guarantees the right level of security for connected systems when the underlying network infrastructure alone can not provide it.

The rationale for using VPN access instead of a private network is usually reduced to cost and viability: It is not feasible to have a private network, for example, for a street sales representative, or it is too expensive to do so. The most common types of VPN are remote access VPNs and site-to-site VPNs.

A remote access VPN uses a public telecommunications infrastructure such as the Internet to provide remote users with protected access to their company’s network. This is essential  when employees use a public Wi-Fi hotspot or other routes to use the internet and connect to their corporate network.

A Virtual Private Network client on the remote user’s computer or mobile device connects to a VPN gateway in the company’s network. The gateway normally needs the device to confirm its identity. Next, you create a network link to the device that allows you to access internal network resources, for example, file servers, printers and intranets, as if you were locally on that network.

How Virtual Private Network (VPN) Works?

A remote access VPN usually relies on IPsec or Secure Sockets Layer (SSL) to secure the connection, although SSL VPNs often focus on providing secure access to a single application, rather than the complete core network.

Few of the VPNs provide Level 2 access to the destination network; these require a tunneling protocol such as PPTP or L2TP, which runs through the improper IP connection.

A site-to-site virtual private network uses a gateway device to connect the entire network at one location to a network at another location, typically a small branch that connects to a data center. The end node devices in the remote location do not need VPN clients because the gateway controls the connection.

Most of the site-to-site VPNs that connect over the Internet use IPsec. It is also common to use MPLS carrier clouds, instead of the public Internet, as the VPN transport from site to site. Here, too, it is possible to have Layer 3 (MPLS IP VPN) or Layer 2 (Virtual Private LAN Service, or VPLS) connectivity running through improper carriage.

Virtual private networks can also be defined between specific computers, usually servers in separate data centers, when the security requests for their exchanges exceed what the business network can offer. Increasingly, businesses also use VPN connections in remote access mode or site-to-site mode to connect or connect to resources in a public infrastructure environment as a service.

The new hybrid access scenarios place the VPN gateway in the cloud, with a secure link from the cloud service provider to the internal network.

Types of virtual private networks (VPNs): 

In general terms, a VPN or Virtual Private Network is a group of computers or discrete networks connected in a public network such as the Internet. A VPN protects your computer’s web connection to ensure that everything you receive and send is encrypted and hidden from prying eyes. More on what a VPN is and why you need one.

So, first, how do you know if you need a VPN? In simple words, anyone from a student to a worker, or someone who wants others to take care of their affairs in relation to their privacy on the internet should get a VPN.

There are several types. The most common VPNs are PPTP, from Site to Site, L2TP, IPSec, MPLS, and hybrid VPN. Let us discuss about each type in detail:

PPTP Virtual Private Network (VPN)

PPTP is the abbreviation of Point-to-Point Tunneling Protocol. As the name implies, a PPTP VPN creates a tunnel and captures the data. A rather long name for the most used VPN. PPTP VPNs are used by remote users to connect to the VPN network through their existing internet network. It is useful for businesses and home use.

To access the VPN, users log in with an approved password. PPTP VPNs are ideal for personal and business use because they do not require the purchase or installation of additional hardware and features usually offered as cheap add-ons. PPTP VPNs are widely used also because of their compatibility with Windows, Mac and Linux.

Although it seems to have many benefits, there is a downside to this VPN, which is, it does not deliver encryption, which is usually the reason why one would get a VPN. Another disadvantage is that it depends on the PPP or Point-to-Point Protocol to implement security measures.

VPN Site to Site

A site-to-site VPN, also called a router-to-router VPN, and is used mostly in corporate operations. Because of the same many companies have offices located inside and outside the country, a site-to-site VPN is used to connect the main office network to different offices. This is also known as intranet-based VPN.

The opposite is also possible with a site-to-site VPN. Companies use it to connect with other companies in the same way, and this classifies as an extranet-based VPN. In simple terms, a site-to-site VPN creates a virtual bridge that links networks in different places to connect them to the internet and maintain secure and private communication between them.

Similar to a PPTP VPN, the Site-to-Site VPN creates a secure network. Though, there is no dedicated line in use that allows different sites within a company to connect to form a VPN, as mentioned above. In addition, unlike PPTP, routing, encoding and decoding is done with routers in the form of hardware or software on both sides.

Virtual Private Network (VPN) L2TP

L2TP is the abbreviation of Tunneling Protocol (in English, Layer to Tunneling Protocol) and was developed by Microsoft and Cisco. L2TP VPNs are typically combined with another VPN security protocol to establish a more secure connection.

An L2TP VPN forms a channel among two L2TP connection points, and another VPN as the IPSec procedure encrypts the data and focuses on ensuring communication among the channels.

An L2TP is also similar to PPTP. The likenesses exist in terms of their lack of encryption and in that both depend on PPP protocols to do so. They begin to differentiate themselves in relation to the confidentiality and integrity of the data. L2TP VPNs provide both, while PPTP VPNs do not.

IPsec

IPsec is an abbreviation of Internet Security Protocol. IPsec is a VPN protocol that is used to protect communication over the Internet through an IP network. A tunnel is established at a remote site that allows access to your central site.

An IPsec works by protecting the communication of the internet protocol by verifying each session and individually coding the data packets during the connection. There are two modes in which an IPsec VPN operates, and they are the transport mode and the tunnel mode. Both modes protect the transfer of data between two different networks.

During transport mode, the message is encoded in the data packet. In tunnel mode, the entire data packet is encrypted. One benefit of using an IPsec VPN is that it can also be used in conjunction with other security protocols to provide a more robust system.

Although an IPsec is a valuable VPN, a major disadvantage of using this protocol are costly and time-consuming facilities on the client side that must exist before use.

SSL and TLS

SSL means Secure Sockets Layer and TLS is the abbreviation of Transport Layer Security. Both work as a protocol, used to create a VPN connection. It is a virtual private network connection where the web browser works as a client. And the user’s access is limited to precise applications instead of being able to access the entire network.

The SSL and TLS protocol is mainly used in shopping websites and service providers. An SSL and TLS VPN gives you a secure session from your PC’s browser to the application’s server. Due to the same web browsers switch to SSL easily and require almost no action on the part of the user. The browsers already come with SSL and integrated TLS. SSL connections have https at the start of the URL instead of HTTP.

MPLS VPN

Multi-protocol label switching (MPLS) VPNs are most effectively used for site-to-site connections. This is mostly because of the point that MPLS are the most flexible and adaptable option. It is a standard base resource used to accelerate the distribution of network packets across multiple protocols. MPLS VPNs are systems that are adjusted to ISP. A virtual private network adjusted to ISP is when two or more sites are connected to form a VPN using the same ISP. However, the biggest disadvantage of using an MPLS VPN is the fact that the network is not as easy to configure compared to other VPNs. It is also not easy to make modifications. Therefore, this type of VPN is usually more expensive.

Hybrid Virtual Private Network (VPN)

A hybrid VPN combines MPLS and VPN based on Internet security protocol or IPsec. Although these two types of VPN are used separately in different sites. However, it is possible to use both in the same place. This would be done with the intention of using the IPsec VPN as an MPLS VPN backup.

The IPsec are VPN that require some equipment by the client of some things mentioned above. This equipment generally comes in the form of a router or multipurpose safety device. Through this router or device the data is encoded and the VPN tunnel is formed as mentioned before. Comparatively, MPLS VPNs are used by an operator, through the equipment in their network.

To connect to these two VPNs, a portal is established to eliminate the IPsec tunnel on one side and trace it to the MPLS VPN at the other end. While preserving the security that this network proposes to provide.

Hybrid VPNs are used by companies mainly because using MPLS for their sites would not be the most appropriate option. There are a lot of advantages that MPLS have over public internet connections, but their cost is high. Therefore, using a hybrid VPN allows you to access the central site through a remote site. Hybrid VPNs are generally expensive, but offer great flexibility.