What is a VPN server. VPN - what is it, server setup

Relatively recently, VPN technologies have become very popular among computer and mobile technology users. Most people, however, don’t really think about why a VPN is needed on a phone, tablet, desktop computer, or laptop, or how it all works. Let's try to consider some aspects of these issues, without going too much into technical terms and descriptions of operating principles.

What is a VPN in general?

The abbreviation VPN is derived from the English phrase, which literally means “private virtual network.” Unfortunately, this term does not fully characterize the organization of such networks, the principles of operation, and why a VPN is needed in general. Yes, of course, some conclusions can be drawn from the definition. In particular, it can be clearly understood that this definition means a network to which a limited number of users have access.

However, this network is not simple, but protected, and in such a way that the transmitted and received data passes through a kind of tunnel in encrypted form, and it is almost impossible to access them outside the network. But this is only a general concept. If you dig deeper, you can find considerable similarities between VPNs and anonymizers or similar proxy servers, which are capable of providing not only information protection, but also the anonymity of the user’s stay on the Internet, naturally, even while hiding traces of visits to certain resources.

Understanding Tunneling Technology

It’s impossible to talk about why a VPN is needed without understanding how it all works, at least at the most primitive level. Therefore, we will briefly dwell on the principles of operation of connections of this type. To simplify the explanation, we will use the following example.

Data transfer from one computer or mobile device to another is carried out exclusively through a special secure channel called a tunnel. At the output, the traffic is encrypted, and at the input, decryption can only be done if there is an appropriate key, which is known only to the sending and receiving parties. Since access to the network is also limited, only registered users can use it.

But, speaking about why you need a VPN at home or in the office and on different devices when working on the Internet, you should especially pay attention to the fact that when using such technologies, the external IP address of the device from which you connect to a specific resource changes. Why is this being done? The fact is that each device, when connected to the World Wide Web, is assigned a unique external identifier (IP address), even dynamically changing, which directly depends on the geographic location of the provider. Based on this, it is not difficult to realize that access to some services or sites in a certain region may simply be blocked. And a VPN allows you to bypass such restrictions.

Why do you need a VPN?

If we talk about the practical side of the need to use a VPN, we can give several specific examples. Let's say you come to a cafe where you can get free access to Wi-Fi, and log into some social network by entering your username and password. Since the public Wi-Fi network itself has a very low level of security, or none at all, it will not be difficult for any competent attacker to gain access to your data by hacking the transmission channel. Okay, if it concerns only such resources. What if you are currently trying to perform some banking transaction using the same mobile application? Where is the guarantee that such information will not be stolen? Now, it probably becomes clear why you need a VPN on your iPhone or Android device. The same applies to all desktop or laptop computers.

Another, albeit sad, example is Ukraine, where relatively recently one of the most ridiculous laws was adopted at the state level to block some Russian social networks (Odnoklassniki, VKontakte) and services, including search and mail services Yandex and Mail.Ru, not to mention the ban on some online information publications. At first, this caused a real shock among the user audience, but then many quickly realized that using a VPN allows you to bypass these restrictions in no time, even without special knowledge in the field of computer technology. Another thing is China and North Korea. In these countries, even a VPN does not help, since they have such powerful firewalls that it is almost impossible to break through their protection.

Another aspect can be associated with the availability of services on the Internet that are available only for certain regions. So, for example, you won’t be able to simply listen to an Internet radio intended for broadcasting exclusively in the United States, since this service is closed for Eastern Europe. That is, after determining your region based on the external IP device from which the connection is attempted, you simply will not gain access to the service. Changing the address by using a VPN client solves this problem easily!

in browsers?

Why do you need a VPN, we figured it out a little. Now let's look at the practical use of such technologies in relation to the most common Internet browsers. For all browsers today you can find a lot of plugins in the form of additionally installed extensions, among which there are specialized VPN clients like friGate, Browsec and the like. The Opera browser compares favorably with all other browsers, in which such a client is built-in.

To activate it for the first time, you must use the security section of the main menu, and to enable or disable it again, use a special switch added to the panel to the left of the address bar. In this case, you can trust the automatic settings or choose your preferred region yourself.

The image above shows an example of accessing the Yandex start page in Ukraine with the client turned off and on. As you can see, bypassing the blocking is simple.

General purpose programs

However, the matter may not be limited only to browsers, since access to the Internet may be required at any time by certain programs installed on a computer or mobile device. The official websites of such applications may also be blocked. In particular, we are talking about updates to Kaspersky Lab antiviruses and Dr. packages. Web. Why you need a VPN in this case is probably clear. Without updating anti-virus databases or security program components, full-fledged protection will simply become impossible. But the installation of updates is not done through the browser, but directly when accessing the resource by the program itself. In such a situation, special applications help by changing the external IP of the computer for all installed applets.

One of the most interesting applications is the SafeIP program, which can configure addresses both automatically and by allowing the user to select a region. This equally applies to all kinds of email clients like Mail.Ru Agent, for which blocking is bypassed using a similar method.

Why do you need a VPN server?

As for servers of this type, their purpose is more to ensure network security by limiting user access and encrypting information. This allows you to more securely protect your own wireless connection. Again, after connecting to such a server, there will be no need to bypass blocking of various levels on individual devices. In addition, this allows you to organize a network based on an Internet connection from different parts of the world.

Creation using Windows

In principle, you can create a server at home even using Windows tools. True, the principles used are somewhat different from what third-party programs offer.

In Windows, you first need to enter the network settings (ncpa.cpl), create a new incoming connection, select a user with the maximum set of administrative rights, activate allowing users to connect via the Internet (VPN), enable the desired TCP/IP protocol and specify the users who will be allowed connection.

To connect, you will initially need to know the Internet address of the created server and your login and password.

Note: this technique only works for devices with static addresses, and in some cases (if the VPN connection is made through a router), you need to open (forward) port 1723 on the router, which directly depends on the model of the router used.

Mobile settings and applications

Finally, let's see why you need a VPN on Android. In principle, the purpose of such technologies is practically no different from conventional computers. The only difference can be in the setting. For example, you can create a server (access point) using the system itself or use third-party applications. For comfortable access to sites, you can use the mobile version of the Opera browser. But why do you need VPN Master - one of the most popular programs for mobile devices?

In a sense, it is an analogue of the SafeIP application mentioned above and allows you to bypass possible restrictions for all services without exception, including news, antivirus updates, listening to Internet radio or music in special applications like Spotify, not designed for use in a specific region.

Imagine a scene from an action-packed movie in which the villain escapes the crime scene along the highway in a sports car. He is being pursued by a police helicopter. The car enters a tunnel that has several exits. The helicopter pilot does not know which exit the car will appear from, and the villain escapes the chase.

VPN is a tunnel connecting many roads. No one from the outside knows where the cars entering it will end up. No one from the outside knows what is happening in the tunnel.

You've probably heard about VPN more than once. Lifehacker also talks about this thing. Most often, a VPN is recommended because using the network you can access geo-blocked content and generally increase security when using the Internet. The truth is that accessing the Internet through a VPN can be no less dangerous than directly.

How does a VPN work?

Most likely, you have a Wi-Fi router at home. Devices connected to it can exchange data even without the Internet. It turns out that you have your own private network, but in order to connect to it, you need to be physically within reach of the router’s signal.

VPN (Virtual Private Network) is a virtual private network. It runs on top of the Internet, so you can connect to it from anywhere.

For example, the company you work for may use a virtual private network for remote workers. Using a VPN, they connect to their work network. At the same time, their computers, smartphones or tablets are virtually transferred to the office and connected to the network from the inside. To log into a virtual private network, you need to know the VPN server address, login and password.

Using a VPN is quite simple. Typically, a company installs a VPN server somewhere on a local computer, server, or data center, and connects to it using a VPN client on the user’s device.

Nowadays, built-in VPN clients are available in all current operating systems, including Android, iOS, Windows, macOS and Linux.

The VPN connection between the client and the server is usually encrypted.

So VPN is good?

Yes, if you are a business owner and want to secure corporate data and services. By allowing employees into the work environment only through a VPN and using accounts, you will always know who did and is doing what.

Moreover, the VPN owner can monitor and control all traffic that goes between the server and the user.

Do your employees spend a lot of time on VKontakte? You can block access to this service. Does Gennady Andreevich spend half his working day on sites with memes? All his activity is automatically recorded in logs and will become an ironclad argument for dismissal.

Why VPN then?

VPN allows you to bypass geographic and legal restrictions.

For example, you are in Russia and want. We regret to learn that this service is not available from the Russian Federation. You can use it only by accessing the Internet through a VPN server in the country in which Spotify operates.

In some countries, there is Internet censorship that restricts access to certain sites. You want to access some resource, but it is blocked in Russia. You can open the site only by accessing the Internet through a VPN server of a country in which it is not blocked, that is, from almost any country except the Russian Federation.

VPN is a useful and necessary technology that copes well with a certain range of tasks. But the security of personal data still depends on the integrity of the VPN service provider, your common sense, attentiveness and Internet literacy.

In this article, I will tell you what is a VPN and why is it needed?.

If earlier the Internet was used to a greater extent only to open a website, find out useful information and perhaps even leave a comment, then today, in principle, nothing has changed. People still open their browser to read interesting and necessary things. However, there is still a difference.

It lies in the abundance of personal and important information passing through the Internet. Therefore, many technologies have been invented to protect them. One of them is VPN, which will be discussed further.

Note: The article is written in simple words and does not contain many technical aspects, as it is intended for initial information.

What is VPN

VPN(Virtual Private Network) is an approach that allows you to organize a private network on top of the main network. In simple words, for example, create a shared private network of computers located in different parts of the world. A more realistic example is the ability to control a computer at home from anywhere from a laptop as if you had never left.

It is worth noting that most often we are talking about a secure connection, since for the most part using a VPN involves transferring data over the Internet. Continuing the example given earlier, when connecting from a laptop via a public WiFi network to your computer in order to download important documents or simply look at photo albums, attackers would not be able to see them.

However, VPN can be used in very specific ways. For example, as I already described in the article how to bypass website blocking, an encrypted connection is created with a certain remote VPN server and this server sends requests to websites. In this case, your IP address and other technical issues remain hidden from the site.

Another important point is that when using a secure VPN, the traffic will be encrypted even for the provider.

How everything happens with a secure VPN

First of all, you should know that there are three types of connection:

1. Node-node. This is a connection between two separate computers (nodes) via a secure VPN.

2. Node-network. In this case, we are talking about the fact that on the one hand there is one computer, and on the other hand a certain local network.

3. Network-network. This is the combination of two local networks into one.

If you are an ordinary user who knows nothing about the network, then it may seem that these types are significantly different. Of course, there are technical nuances, but for a simple understanding, all these networks can be reduced to one “Node-node”. The fact is that in the case of a network, just a computer or router through which Internet access is provided also organizes and carries out communication via VPN. That is, computers inside the network may not even know about the presence of any VPN.

Now, let's look at how everything happens when using a VPN (in general):

1. Special programs are installed and configured on computers to create a VPN tunnel (in simple words, a VPN connection). If this is a router, then many specialized models natively support such connections.

Note: It is worth knowing that there are three types of programs: “client” (only connects to other computers), “server” (provides and organizes access for VPN clients) and “mixed” (can both create connections and receive them).

2. When a computer wants to communicate with another computer, it contacts the VPN server to establish an encrypted tunnel. As part of this step, the client and server exchange keys (in encrypted form), if necessary.

4. The VPN server decrypts the original data and acts based on it.

5. The server also encrypts its response and transmits it to the client.

6. The client decrypts the response.

As you can see, the basic idea of ​​a VPN is very simple - keys are exchanged, and then the client and server send encrypted messages to each other. However, it gives a huge advantage. Except for the IP address of the VPN client and server, all data is transmitted in private form, that is, the security of the transmission of personal and important information is ensured.

Why do you need a VPN?

VPN is usually used for the following two purposes:

1. Secure data transmission on the Internet. The data is initially transmitted in encrypted form, so even if an attacker can intercept it, he will not be able to do anything with it. A well-known example is HTTPS with SSL or TLS to access sites. In this case, a secure VPN tunnel is established between the site and the computer that opened it, so the data is safe at the time of transmission.

Note: HTTPS means that data is encrypted with SSL or TLS and then sent in a standard manner, just like HTTP.

2. Connecting computers from different parts of the world into one network. Agree that it can be very useful to have access to computers located hundreds of kilometers away from you at any time. For example, so as not to carry everything you need with you. If you need photos or some documents, go online, connect to your home computer and download them in safe mode. Or, for example, if you have two networks, then by combining them using routers (creating a VPN tunnel), you can access any computer without any additional actions.

In the 21st century, information technologies occupy an integral place in the life of almost any person. Even an 80-year-old grandmother from a village who does not know how to turn on a computer is indirectly connected with them. Databases, bank accounts, messenger accounts - all this requires a high level of security. The Internet, which has grown to a global scale, like any other mechanism, becomes more vulnerable as its design becomes more complex. To protect confidential information, VPN technology was invented.

VPN connection (from the English Virtual Private Network - virtual private network) is a technology that allows you to artificially form a local network of Internet participants who are not physically connected by a direct connection. This is an add-on to the global network that provides communication between nodes that appears direct from the client side.

How a VPN connection works

A VPN virtual network works on the principle of establishing a fixed connection. Communication can be established directly, between two nodes of the same level (on a network-to-network or client-client basis), or (more commonly) between a network and a client. One of the elements (the connection initiating server) must have a static (permanent) IP address at which other network nodes will find it. An access point is created on the server in the form of a gateway with Internet access. Other network participants join it, the connection is made in the form of an isolated tunnel.

For all switching nodes through which data packets pass, the information is encrypted. It is transmitted in the form of an unintelligible stream, the interception of which will give hackers nothing. Encoding-decoding keys for many protocols (for example, OpenVPN) are stored only on end devices. And without them, attackers cannot do anything with the intercepted data. For maximum security, an archive with certificates and keys (without which it will not be possible to install a secure VPN) can be sent in encrypted form, or manually transferred to a flash drive. In this case, the likelihood of unauthorized access to network computers is reduced to zero.

Why do you need a VPN?

Direct communication

On the Internet, the physical distance between participants and the complexity of the route along which they exchange data do not matter. Thanks to IP addressing and DNS nodes, you can access another computer on the World Wide Web from anywhere in the world. The level of security of the connection is much more important, especially when exchanging confidential information. The more switching points (routers, gateways, bridges, nodes) data passes through, the higher the likelihood of it being intercepted by attackers. Having the physical parameters of a PC or server (for example, its IP address) - through vulnerable connection methods, hackers can penetrate it by breaking password protection. It is precisely from such attacks that the VPN protocol is designed to protect.

Unblocking access to resources

The second function of VPN networks is to open access to blocked resources. If there is Internet censorship in one form or another on the territory of a country (as in China), its citizens may be limited in access to certain resources. Accessing the network through foreign VPN servers allows you to avoid the threat of reprisals to representatives of opposition forces in totalitarian countries. State authorities that interfere with freedom of speech (as in China or the DPRK) will not be able to bring charges of viewing “ideologically harmful” resources, even if providers provide them with a backup of all intercepted data.

Some online services may block access to customers from countries and regions where they are not officially present. This is sometimes done by online games, international payment systems, trading platforms, online stores, online distribution systems for digital content (music, films, games). A VPN server based in a country where access is open removes such restrictions and allows you to make purchases.

Protection against hacking of private resources

Another reason why private clients need a VPN connection is remote administration. If you want to protect your server as much as possible from outside interference, you can create a “white list” of IP addresses that have access to it. When one of them (addresses) belongs to a private VPN server, you can safely connect to the administered server from anywhere in the world using encrypted communication. The administration object will consider that it was connected to from an authorized terminal, and the administrator does not have to worry about the risk of hacking.

Protection of trade secrets

VPN protocols are in demand in commercial structures that work with money and economic secrets. The virtual secure network prevents hackers from hacking accounts or finding out industrial secrets and technologies. Employees who, due to their duties, need to gain access to the company’s network resources from home or on a business trip, can organize a connection via VPN without exposing the corporate network to the threat of hacking.

Every year electronic communications are improving, and increasingly high demands are placed on information exchange for speed, security and quality of data processing.

And here we will look at a VPN connection in detail: what it is, why a VPN tunnel is needed, and how to use a VPN connection.

This material is a kind of introductory word to a series of articles where we will tell you how to create a vpn on various operating systems.

VPN connection what is it?

So, a virtual private network vpn is a technology that provides a secure (closed from external access) connection of a logical network over a private or public one in the presence of high-speed Internet.

Such a network connection of computers (geographically distant from each other at a considerable distance) uses a “point-to-point” connection (in other words, “computer-to-computer”).

Scientifically, this connection method is called a VPN tunnel (or tunnel protocol). You can connect to such a tunnel if you have a computer with any operating system that has an integrated VPN client that can “forward” virtual ports using the TCP/IP protocol to another network.

Why do you need a VPN?

The main benefit of a vpn is that negotiaters need a connectivity platform that not only scales quickly, but also (primarily) ensures data confidentiality, data integrity, and authentication.

The diagram clearly shows the use of VPN networks.

Rules for connections over a secure channel must first be written on the server and router.

How VPN works

When a connection occurs via VPN, the message header contains information about the IP address of the VPN server and the remote route.

Encapsulated data passing over a shared or public network cannot be intercepted because all information is encrypted.

The VPN encryption stage is implemented on the sender's side, and the recipient's data is decrypted using the message header (if there is a shared encryption key).

After the message is correctly decrypted, a VPN connection is established between the two networks, which also allows you to work on a public network (for example, exchange data with a client 93.88.190.5).

As for information security, the Internet is an extremely unsecured network, and a VPN network with the OpenVPN, L2TP / IPSec, PPTP, PPPoE protocols is a completely secure and safe way to transfer data.

Why do you need a VPN channel?

VPN tunneling is used:

Inside the corporate network;

To unite remote offices, as well as small branches;

For digital telephony services with a wide range of telecommunications services;

To access external IT resources;

For building and implementing video conferences.

Why do you need a VPN?

VPN connection is required for:

Anonymous work on the Internet;

Downloading applications when the IP address is located in another regional zone of the country;

Safe work in a corporate environment using communications;

Simplicity and convenience of connection setup;

Ensuring high connection speed without interruptions;

Creating a secure channel without hacker attacks.

How to use VPN?

Examples of how VPN works can be given endlessly. So, on any computer in the corporate network, when you establish a secure VPN connection, you can use mail to check messages, publish materials from anywhere in the country, or download files from torrent networks.

VPN: what is it on your phone?

Access via VPN on a phone (iPhone or any other Android device) allows you to maintain anonymity when using the Internet in public places, as well as prevent traffic interception and device hacking.

A VPN client installed on any OS allows you to bypass many of the provider’s settings and rules (if the provider has set any restrictions).

Which VPN to choose for your phone?

Mobile phones and smartphones running Android OS can use applications from Google Playmarket:

• - vpnRoot, droidVPN,
• - tor browser for network surfing, also known as orbot
• - InBrowser, orfox (firefox+tor),
• - SuperVPN Free VPN Client
• - OpenVPN Connect
• - TunnelBear VPN
• - Hideman VPN

Most of these programs are used for the convenience of “hot” system setup, placing launch shortcuts, anonymous Internet surfing, and selecting the type of connection encryption.

But the main tasks of using a VPN on a phone are checking corporate email, creating video conferences with several participants, and holding meetings outside the organization (for example, when an employee is on a business trip).

What is VPN on iPhone?

Let's look at which VPN to choose and how to connect it to your iPhone in more detail.

Depending on the type of network supported, when you first start the VPN configuration on your iPhone, you can select the following protocols: L2TP, PPTP and Cisco IPSec (in addition, you can “make” a VPN connection using third-party applications).

All of the listed protocols support encryption keys, user identification using a password and certification are carried out.

Additional features when setting up a VPN profile on an iPhone include: RSA security, encryption level, and authorization rules for connecting to the server.

For an iPhone phone from the appstore, you should choose:

• - a free Tunnelbear application with which you can connect to VPN servers in any country.
• - OpenVPN connect is one of the best VPN clients. Here, to launch the application, you must first import RSA keys via iTunes into your phone.
• - Cloak is a shareware application, since for some time the product can be “used” for free, but to use the program after the demo period has expired, you will have to buy it.

VPN creation: selection and configuration of equipment

For corporate communications in large organizations or combining offices remote from each other, they use hardware equipment that can support continuous, secure work on the network.

To implement VPN technologies, the role of a network gateway can be: Unix servers, Windows servers, a network router and a network gateway on which VPN is installed.

A server or device used to create a VPN enterprise network or a VPN channel between remote offices must perform complex technical tasks and provide a full range of services to users both on workstations and on mobile devices.

Any router or VPN router must provide reliable operation on the network without freezes. And the built-in VPN function allows you to change the network configuration for working at home, in an organization or in a remote office.

Setting up VPN on the router

In general, setting up a VPN on a router is done using the router’s web interface. On “classic” devices, to organize a VPN, you need to go to the “settings” or “network settings” section, where you select the VPN section, specify the protocol type, enter the settings for your subnet address, mask and specify the range of IP addresses for users.

In addition, to secure the connection, you will need to specify encoding algorithms, authentication methods, generate negotiation keys, and specify the WINS DNS servers. In the “Gateway” parameters you need to specify the gateway IP address (your own IP) and fill in the data on all network adapters.

If there are several routers in the network, you need to fill out the VPN routing table for all devices in the VPN tunnel.

Here is a list of hardware equipment used to build VPN networks:

Dlink routers: DIR-320, DIR-620, DSR-1000 with new firmware or D-Link DI808HV Router.

Routers Cisco PIX 501, Cisco 871-SEC-K9

Linksys Rv082 router with support for about 50 VPN tunnels

Netgear router DG834G and routers models FVS318G, FVS318N, FVS336G, SRX5308

Mikrotik router with OpenVPN function. Example RouterBoard RB/2011L-IN Mikrotik

VPN equipment RVPN S-Terra or VPN Gate

ASUS routers models RT-N66U, RT-N16 and RT N-10

ZyXel routers ZyWALL 5, ZyWALL P1, ZyWALL USG