VPN Terminology Guide – AES, OpenVPN, Ciphers and More

We all know that VPNs are great for online safety and security. Despite the fact that VPN’s, aka virtual private network, popularity has surged in the past few years, many people are still clueless about even the most common terms used with VPNs. To help the common VPN user, we came up with a list of the most important and common VPN terms in use today. We won’t be offering a detailed technical analysis of each term in this VPN Terminology guide, but rather a simply explanation that VPN beginners can easily comprehend.

VPN Terminology Guide – AES, OpenVPN, Ciphers and More

VPN Terminology Guide – AES, OpenVPN, Ciphers and More

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VPN Terminology Guide – AES, OpenVPN, Ciphers and More

Below you can find a list of terms often associated with VPN usage. If you more questions about any of these words and their meaning, feel free to drop us a comment below.


AES stands for Advanced Encryption Standard. This is the most advanced and most widely endorsed encryption system in the world at present. Sanctioned by the US government in 2002, it is widely used by VPN providers all over the world.


This is where you get to remain untraceable as well as all your online activity. You’re anonymous when you’re untraceable on the internet.


The biggest name in the cryptocurrency market right now, Bitcoin runs as a payment and investment method and allows a relatively high degree of anonymity to users.


Suppressing of freedoms by government bodies or important institutions. It can lead to physical assaults and even jail time, so internet anonymity is of major significance.


A certain algorithmic pattern or code utilized for encryption connections between server and clients. AES is an example.


The scientific study of mathematically secured communications.

Dark Web

An aspect of the internet only accessible through secure software like and Tor.

Data Retention

Legal frameworks based on which companies retain user-related data. Most Internet Service Providers or ISPs are mandated by law to retain user data for at least a few months.

Dedicated Server

A single-user oriented server meant to host all the online activity of that user.

Deep Package Inspection

Individual inspection of data packets to eliminate interception by other parties as well as malware of any kind. Also done for censorship and identifying any involved parties.

DNS Leak

A situation wherein an improper configuration of a VPN leads a user to reveal their identity on a site they happen to visit by chance. You want to avoid DNS leaks when using a VPN.


Coding of information to allow selective access only to designated persons. Mostly accomplished through mathematical data abstraction, primes, and covert numbering.

Encryption Key Length

This denotes the size of the key used to decrypt the data and is generally measured in bits. Symmetric systems such as AES have keys of 128, 256, and 512 bits. For others, they vary between 1024 to 4096 bits.

End-to-End Encryption

An encrypted tunnel which can only be accessed by two users at either end of the tunnel. All communication between these two points is completely encrypted.


These are systems that are established either to protect an infrastructure or simply restrict content for some users or selected groups. Firewalls also investigate all inbound and outbound traffic to ensure system integrity.

Five Eyes

A group of five powerful nations formed back during the World War II era. Snowden’s revelation that these countries were spying on each other’s citizens and then giving each other the info showed how these governments were bypassing the legal restrictions on spying imposed by the law.


Blocking of online content or services by companies according to physical locations of individuals. This is the reason why you cannot access Hulu from outside US and Japan. A VPN can bypass geoblocking.

Great Firewall

The Great Firewall of China, which restricts external content from being accessed and also protects the country’s intranet from external attacks.


An agreement between two channels of communication. For VPNs, this also includes verification of the integrity of each communication made.


Basic end-to-end tunneling protocol. Denoted by a lock symbol before the web address. Generally, HTTPS before a URL means that a website is secure.

IP Address

Distinct Id for a network device. Identified using LAN to router to the internet. When you open a website, it can see your IP address and thus your location.

IP Leak

Improperly routed data can leads to leaks when the data bypasses the tunnel to reach the intended destination, thus revealing the actual IP.


ISP basically stands for Internet Service Provider. The company that provides internet services to you. Your ISP also is responsible of your public IP address.

Kill Switch

A frequently used feature in VPNs to make sure data does not get routed after the connection is breached or finished. All good VPN services provide kill switches.


Record of all internet activity on a server. Entails ethical questions of how much data retention is or should be legal.


Popular VPN protocol which uses HTTPS-like tech and is regularly updated by a dedicated community. Very handy in bypassing censorship.

P2P Software

Peer-to-peer software used for direct contact between two users without commercial servers. Bittorrent for instance relies on P2P in order to send and receive data. Keep in mind that not all VPN service providers support P2P.


Data chunks broken down by IPv4 and IPv6 protocols disassembled before transmission and reassembled after delivery completion.


Data transmission device which can be configured to connect to a VPN service provided the firmware supports it.


Asymmetrical encryption standard first created in 1977 but still in use. It’s a public key technology that is widely used by VPN providers.

Simultaneous Connections

VPN term for the number of devices which can be linked up to the service by a user at the same time.


Secure Socket Layer. Outdated by TLS. It was previously used for standard HTTPS.


Secure Socket Tunneling Protocol which uses PPTP inside HTTPS for more secure connections.


Anonymous browsing software which uses HTTP proxies to bounce off the data and hide the IP address.


A secure connection between you and any other network.

VPN Client

VPN service user who connects with the VPN service provider before accessing the net.

Warrant Canary

A disclosure policy in case the government places a gag order on the company and puts user data integrity at risk. If the disclosure is not regularly updated or the canary is pulled down, the company has got a gag order.


Wi-Fi Protected Access 2 – a prevalent encryption and selective accessing protocol used for secure internet access and limit access.

VPN Terminology – A Beginner’s Guide

As you’re now familiar with the most common terms linked with VPNs, we hope you’ll make a better choice when you select a VPN provider. You might come across some VPN-related terms that aren’t listed in the guide above. Feel free to leave a comment below for more info about anything concerning virtual private networks.

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