You probably use some form of encryption almost every day, and you probably dont even think about it. But what is it and how does it work Types of Encryption. There are two main ways to do encryption today. The first kind of encryption, called symmetric cryptography or shared secret encryption, has been. VPN Encryption The Complete Guide  Best. VPN. com. A Virtual Private Network VPN encrypts all data as it travels between your computer and a VPN server. In this Complete VPN Encryption Guide, I take a detailed look at what encryption is, and how it is used in VPN connections. Perhaps most importantly, I will explain the confusing array of encryption terms used by VPN services. This confusion is not helped by the fact that many VPN providers can be slapdash to the point of misleading when describing the encryption they use. It is my aim that, after reading through this document, you will have a greater understanding of this complex subject. It is also my hope that you will have a much more critical eye when assessing the security claims made by VPN providers. Preliminaries. If you are unsure about what a VPN is and what one can do for you, please check out my VPNs for Beginners guide. In this article, I use the terms computer and device interchangeably. In doing so, I refer to any internet enabled device that is capable of running a VPN client. This includes desktop PCs, laptops, i. Pads, smartphones, and the like. My aim is to present the key features of VPN encryption in as simple terms as possible. By now it should be clear that encryption isnt just for security geeks and IT administrators. You can take precautions to secure your own most sensitive. In the world of embedded and computer security, one of the often debated topics is whether 128bit symmetric key, used for AES Advanced Encryption Standard is. A Virtual Private Network VPN encrypts all data as it travels between your computer and a VPN server. In this Complete VPN Encryption Guide, I take a detailed look. What is encryption, what are encryption keys and how to stay safe online. In cryptography, key size or key length is the number of bits in a key used by a cryptographic algorithm such as a cipher. Key length defines the upperbound on an. A09D43D000005DC-124_634x395.jpg' alt='How Long Would It Take To Crack 256 Bit Aes Encryption Crack' title='How Long Would It Take To Crack 256 Bit Aes Encryption Crack' />There is no getting away, however, from the fact that encryption is a horribly complex subject. It not for the technically faint of heart If even the term encryption causes your eyes to start glazing over, but you still want to know what to look out for in a good VPN service, you can jump straight to my summaries. What Is EncryptionBegin at the beginning, the King said, very gravely, and go on till you come to the end then stop. Lewis Carroll, Alice in Wonderland. The simplest analogy is that encryption is a lock. If you have the correct key, then the lock is easy to open. If someone does not have the correct key but wants to access the contents of a strong box that is, your data protected by that lock, then they can try to break the lock. In the same way that the lock securing a bank vault is stronger than the one securing a suitcase, some encryption is stronger than other encryption. The Basics. When you were a kid, did you play the game in which you created a secret message by substituting one letter of the message with another The substitution was made according to a formula picked by you. You might, for example, have substituted each letter of the original message with one three letters behind it in the alphabet. If anyone else knew what this formula was, or was able to work it out, then they would be able to read your secret message. In cryptography jargon, what you were doing was encrypting the message data according to a very simple mathematical algorithm. Cryptographers refer to this algorithm as a cipher. To decrypt it you need the key. This is a variable parameter which determines the final output of the cipher. Without this parameter, it is impossibble to decrypt the cipher. If someone wants to read an encrypted message but does not have the key, then they must try to crack the cipher. When the encryption uses a simple letter substitution cipher, cracking it is easy. The encryption can be made more secure, however, by making the mathematical algorithm the cipher more complex. You could, for example, substitute every third letter of the message with a number corresponding to the letter. Encryption Key Length. Modern computer ciphers are very complex algorithms. A09DD00000005DC-58_634x247.jpg' alt='How Long Would It Take To Crack 256 Bit Aes Encryption Crack' title='How Long Would It Take To Crack 256 Bit Aes Encryption Crack' />Even with the help of supercomputers, these are very difficult to crack, if not impossible for all practical purposes. The crudest way to measure the strength of a cipher is by the complexity of the algorithm used to create it. The more complex the algorithm, the harder the cipher is to crack using a brute force attack. This very primitive form attack is also known as an exhaustive key search. It basically involves trying every combination of numbers possible until the correct key is found. As Im sure we all know, computers perform all calculations using binary numbers  zeros and ones. Adobe Photoshop Separation Setup File. The complexity of a cipher is measured by its key size in bits the raw number of ones and zeros necessary to express its algorithm, where each zero or one is represented by a single bit. This is known as the key length, and also represents the practical feasibility of successfully performing a brute force attack on any given cipher. The number of combinations possible and therefore the difficulty to brute force them increases exponentially with key size. Using the AES cipher see later To put this into perspective In 2. Fujitsu K. This was capable of an Rmax peak speed of 1. Based on this figure, it would take Fujitsu K 1. AES Advanced Encryption Standard key by force. This is older than the age of the universe 1. The most powerful supercomputer in the world now 2. Sunway Taihu. Light in China. This beast is capable of a peak speed of 9. This means that the most powerful computer in the world would still take some 8. AES key. The number of operations required to brute force a 2. This is roughly equal to the number of atoms in the universe Computer Ciphers. While encryption key length refers to the amount of raw of numbers involved, ciphers are the mathematics the actual formulas or algorithms used to perform the encryption. As we have just seen, brute forcing modern computer ciphers is wildly impractical. It is weaknesses sometimes deliberate in these cipher algorithms that can lead to encryption being broken. This is because no encryption key is completely random. They use pseudo random numbers which are themselves calculated using known algorithms. This creates a reduced set of possible outcomes, which in effect reduces the key length. The Blowfish cipher, for example, is vulnerable to an attack that exploits the mathematics behind the birthday problem in probability theory. The study of weaknesses in cryptographic algorithms is known as cryptoanalysis. Longer key lengths compensate for such weaknesses, as they greatly increase the number of possible outcomes. Cipher Key Length. How strong a cipher is depends on both the mathematics of the cipher itself, plus its key length as expressed in bits. For this reason, ciphers are usually described along with the key length used. So AES 2. 56 the AES cipher with a 2. AES 1. 28. Note that I say usually because we are dealing with very complex mathematics here see my notes on AES later. It is important to note that key length alone is not a good indicator of a ciphers strength. It is the combination of key length and cipher that matters. Ciphers used for asymmetric encryption, for example, use much longer key sizes than those used for symmetric encryption to provide the equivalent protection. This table is a little out of date, as it does not take into consideration newer attacks that have been discovered on RSA. It is also worth noting that elliptic curve and Diffie Hellman variants of RSA are much stronger than traditional ones. But hopefully you get the idea. One thing to note is that the higher the key length, the more calculation involved, so the more processing power needed. This impacts the speed at which data can be encrypted and decrypted. VPN providers and suchlike must, therefore, decide how best to balance security vs. I will discuss the main ciphers used by various VPN protocols a little later. By far the most common ciphers that you will likely encounter with regards to VPNs are Blowfish and AES. In addition to this, RSA is used to encrypt and decrypt a ciphers keys, and SHA 1 or SHA 2 is used as the hash function to authenticate data. Asymmetric encryption. Perfect Forward Secrecy. Perfect Forward Secrecy PFS is also referred to as using ephemeral encryption keys, or just Forward Secrecy FS by those uncomfortable with using the word perfect. Most modern secure online communication relies on SSLTLS. It is used by HTTPS websites and the Open. VPN protocol. TLS Transport Layer Security is an asymmetric encryption protocol.