What is a VPN kill switch?

By opting for a VPN, Internet users choose an anonymous and secure connection. However, Internet connection instabilities can override VPN protection and expose users’ private data without them realizing it.

This is where the kill switch comes in, an option that is now essential to guarantee the security and integrity of personal, sensitive and confidential information. We even find the kill switch within free VPNs.

Closely monitored online activities

Traditionally, when browsing the web, the connection leaves the computer or mobile device, passes through the ISP’s servers, queries the servers of the called domain and returns the response using the reverse path. In this configuration, several entities access different data and metadata allowing the Internet user to be identified and their online activities to be traced.

We first think of the Internet service provider, responsible for assigning an IP address to the device that connects to the Internet. This identification number is used both to establish communication between two computers (here, the PC or mobile device from which the request originates and the servers of the contacted website), and to link the connection to a contract. ‘subscriber. The ISP is also able to monitor traffic passing through its servers. Although it cannot access the content of the request as such, it records connection times and times, determines the addresses of the web pages consulted, takes note of geolocation data, knows what type of device is used to surf. You should also know that in France, the law requires ISPs to collect and keep this connection data for one year.

The websites visited, for their part, access the geolocation information of the Internet user and deduce the type of device used to connect using their public IP address. They also record the online activities of their visitors (dates and times of connections, time spent on a page, number of pages viewed), cross-reference the information recorded over time, refine the sketched user profiles and derive their income from the resale of this data to third-party advertisers.

Sometimes a third undesirable person comes along: the hacker. Capable of hacking unsecured connections, particularly those established by public Wi-Fi, it can easily inject viruses and other malicious programs onto the Internet user’s device in order to recover confidential information (banking codes, personal identifiers, etc. .).

VPN connection, 100% secure private data?

One of the solutions to counter these more or less worrying forms of surveillance is to use a VPN. These services promoting anonymity and security of private data act as an intermediary between the ISP and the rest of the web.

This intermediary consists of an encrypted and secure server, allocating a fake IP address to the Internet user who wishes to surf without feeling like they are being spied on. In detail, the ISP always knows that its subscribers initiate an Internet connection at a specific date and time. However, instead of the address of the sites visited, it is the address of the VPN server that is returned. Same lure for the websites consulted which no longer access the IP of the user, but that provided by the VPN. Please note that a VPN server generally assigns an identical IP to several Internet users (shared IP). Individual traffic is, in fact, buried in the mass of active users on the same server.

The connection between the computer, or mobile device, and the VPN server is made through the establishment of an encrypted tunnel, isolated from the rest of Internet traffic, inside which the data packets, also encrypted, circulate . This double locking should help protect sensitive information against all interception attempts, whether from hackers or official authorities. Traffic leaving the VPN server is decrypted before passing through the public network. However, since it is attached to the IP provided by the VPN, it remains very difficult to determine its origin.

Despite everything, the protection provided by a VPN is based on another criterion independent of the service: the quality of the Internet connection. In theory, as long as the connection is stable, the VPN tunnel remains effective. On the other hand, a power outage, an insignificant network change, an unexpected restart of the box, an imperceptible loss of signal risks disconnecting the VPN and temporarily exposing the identity and private data of Internet users as long as the connection to the security service has not been restored.

The kill switch, the essential for serious VPNs

Secondly, the kill switch preserves the secrecy around the real identity of the Internet user. Interrupting the VPN connection could in fact reveal the real IP address of users to the websites consulted, but also their geolocation. Valuable information to form the basis of a monetizable profile, as explained previously.

The best VPNs with a Kill Switch

CyberghostVPN

NordVPN

ProtonVPN

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