What is a VPN and why is it necessary?

VPN is now more relevant than ever before. Even home routers began to appear not just VPN, but also with hardware-accelerated encryption. Of course, many use mobile applications, such as The SuperVPN Free VPN Client, but they do not fully understand how they work. What is a VPN and why is it required? Try to tell in simple words.

What is a VPN?

As it so happened, that even the textbooks do not give a broader and broader definition of what it means, VPN. They say, and so it is pretty clear: the acronym VPN stands for Virtual Private Network, a virtual private network. And why is something else to discuss? What is “network” — it is clear: on a basic level it is an Association of two or more nodes in any communication so they could share information. Of course, the most convenient way and enabled all services.

What is “private”, also it seems to be obvious — not public, and therefore private. That is, such in which is not just anybody, but only authorized nodes. If you dig a little deeper, then this component of the VPN and is the most important, as it determines the number of requirements for this “particular”.

First, it is necessary to label the members of this network and the information they exchange that it is not mixed with someone else’s. Secondly, this is useful information to protect from prying eyes. Well, at least encrypt that again imposes the following round of restrictions associated with the durability of this encryption.

Thirdly, it is necessary to preserve the integrity of this method of information transfer — not let outsiders into the private network, to check the source of the transmitted messages and to ensure that information is never leaked to “the Nude”. In General, as with private parties from the high noise throughout the neighborhood, and who and what is doing there is not clear. And the harsh guards at the entrance and exit are satisfied not only face but also other control.

With the concept of “virtual” everything a little easier. It just means that such a network abstracted from physical component — it does not matter how many channels it has, as for the actors in this network, it works transparently. Or, on the other hand, physical system, often do not belong to the user virtual.

For example, in significant organizations employees when you connect your laptop to any wired or wireless networks outside the walls of the organization, be obliged immediately to use a VPN connection to the office network. It does not matter, using what the jungle will have this connection, but there is no doubt that it’ll go in public, other people’s networks. Such a relationship is called a tunnel, later this term we will meet again and again.

What is a VPN?

The above example of connecting a remote user to a corporate network is one of the most typical scenarios for using VPN. The user feels like home — instead, at home, on vacation or on a business trip he can feel like work and can easily use the corporate services.

At the same time and the attacker would not be able to sniff out what exactly is busy the user is, what data it sends and receives. Moreover, companies who are concerned about their safety, all workers used the devices will be forced mandatory use of VPN connections anywhere. Even the use of the Internet, in this case, it goes through the corporate network and under the strict supervision of the security service!

The second most common use case was similar, only connect to the corporate network, not individual users, but entire offices or buildings. The goal is the same — to reliably and securely connect geographically separated members of one organization into a single network.

It can be an as broad a representation of corporations in different countries, and scattered around the city meat stalls open company “Horns and hoofs”. Or even just a camera, alarm, and other security systems. With this easy to create a VPN good cable each time to stretch is not necessary — the virtual private network can create and within companies for the Association and isolation of individual departments or systems.

Not less than often organized the VPN networks and between servers or entire compute cluster to maintain availability and data duplication. The frequency of their use is directly connected to the popularity of cloud technology. All of the above is not some workarounds: such connections can be supported (and supported) over the years.

However, now there is a move to the next level of abstraction — SDN (Software Defined Networks, software-defined networking), which will present many more surprises in equal measure and not very pleasant. However, it is a separate and vast topic, to touch on where we are now will not.

USA has its unique way you use a VPN in practice. Once large ISPS have built their networks based on simple unmanaged switches — it is obvious, to save. For separation of the customer, traffic began to use different options VPN connections to the server provider and was given access to the Internet.

Surprisingly, such a method still in use today, manufacturers of home routers for the USA region still have to add support for these connections in the firmware of their devices. So in a sense, USA was the leader in the number of simultaneous VPN connections among the Network users.

A counterexample of such permanent VPN connection is the session connection. They are often used when providing client access to various services that usually are associated with the processing of sensitive information in the field of Finance, health, and law.

However, for the average user is much more important than another variant of the practical use of VPN. In our safety tips for Android and iOS is highly recommended to use a secure VPN connection to a trusted site (whether it is a home router or a VPN provider) when connecting to any public network to protect your traffic against possible interference of intruders!

Finally, the last option uses a VPN in private is a variety of bypass network restrictions. For example, to gain access to resources that are blocked or do not provide their services in a particular area. According to a report by GlobalWebIndex, 2014 to access social media VPN used about 166 million people.


In General, it is evident that VPN is now — a thing useful and are continually gaining popularity. Of course, we talked about this technology and its capabilities in General — in real life there are many nuances associated with its use, including the legislative, and not just technical. And indeed, our story would be incomplete without a description of the popular VPN implementations and development. This is what we will discuss in the next two parts of our series.

Author: Jenny Doe