VPN or Virtual Private Network is a private network built on the infrastructure of a public network. This is a way of connecting two computers over a public network, such as the Internet. Instead of performing this procedure through dedicated links or packet networks, such as Frame Relay and X.25, the Internet infrastructure is used to connect distant and remote networks.
The Virtual Private Network has the great advantage of being much cheaper than dedicated links. Besides, the Internet is present all over the world, with access points scattered everywhere. VPN networks are widely used by large companies, especially in companies where employees work remotely, either on the streets or in the home office system, to connect to the internal structure even when they are far away. Ordinary users also take advantage of the technology of VPN networks to build virtual private networks.
The cost-benefit level of VPN networks compared to dedicated links increases as the distances between connections also increase. Dedicated links are costly, although they have better privacy and security compared to Virtual Private Networks. Because it is based on a public network, where there is an enormous amount of data traffic that can be transmitted and received by any equipment today, VPN does not provide a high level of reliability and security for the information that passes through it.
However, through the encryption of information and communications between hosts on the private network, it is possible to considerably increase the confidentiality of the data that travels over the web. Through the tunneling system, data can be sent without other users having access, and even if they do, they will still receive them encrypted. Therefore, the devices responsible for taking care of the VPN network must guarantee the security and integrity of the information and data that are transmitted.
IPSec (IP Security Protocol) is a suite of protocols created for the construction of secure tunnels over Internet and intranet networks. This tool allows all data to pass through the gateway to be encrypted before going through the path to the destination machine or decrypted before receiving the data.
Another problem that the VPN network can bring is related to the dependence on the speed of the Internet available, especially if the amount of traffic it sends is quite large. Therefore, some companies may have difficulties in using it if their connections are not stable and fast.
Bad connections can lead to technical problems and delays without the user having control over it. Obviously, to create a VPN network, it is necessary to have at least two computers connected to the Internet, in addition to a VPN network management program installed on each machine.
To send the data, the program encrypts and encapsulates the information and adds the IP number of the sending machine so that the target computer can identify who sent the data. Through the tunneling system, data travels through the path until it reaches the receiving machine, which immediately identifies the IP information that was sent by the sending device. After that, the reverse process is performed, with “decryption” and data storage on the destination computer.