What is encryption?

Encrypting data means getting it transformed into a string of characters undecipherable by others.

What actually happens is that by using a secret-key i.e. the equivalent of a code (see glossary), the cryptography system transforms your data into gibberish. If the scrambling of the data is done properly, the original file can only be unscrambled and read by someone who knows the secret key i.e. the code used to encrypt the file.

Encrypting a file ensures that even if someone gets access to your computers/he would not be able to read the data stored there. Encrypted files can safely be sent by e-mail or placed on a network with the assurance that the data can be read only by those who were meant to have it.

Basic encryption systems have been used to protect secrets for many centuries. But today's encryption methods are far more sophisticated and reliable than ever before because the encryption code itself is a very complex computational transformation that is only feasible with desktop machines in the early 1990s

How does encryption work?

When you use encryption, your data gets converted into meaningless symbols by using a key, which is nothing but the code that helps you to encrypt or decrypt data.

The more random the method of key conversion, the stronger the encryption will be. A pass phrase generally needs to be easy to remember, so it has significantly less randomness than its length suggests. For example, a 20-letter English phrase, rather than having 20 x 8 = 160 bits of randomness, only has about 20 x 2 = 40 bits of randomness.

So, cryptographic software converts a pass phrase into a key through a process called ``hashing'' or ``key initialization.'' (see glossary)

At the heart of the process is the algorithm (see glossary), which is devised so as to make deciphering the encrypted file impossible without using the secret key. Some of the popular encryption algorithms include Blowfish, DES, Diffie-Hellman, IDEA, RC4, RSA and Skipjack. Many of these use 64 and 128 bit encryption systems i.e. devise keys of 2*64 or 2*128 length.

The Blowfish encryption algorithm on which CryptoExpert is based was specially designed to encrypt data on 32-bit microprocessor. It is significantly faster than DES and GOST when implemented on 32-bit microprocessors, such as the Pentium or Power PC.

Is encryption safe?

I n ordinary user may find it difficult to unscramble even a simple algorithm. However, experts using sophisticated methods can employ a number of means to break an algorithm. The most common of these is "brute force" wherein a number of computers are simultaneously employed to break the code by a "trial and error" system which physically checks all possible combinations.

However, a well developed encryption system can withstand even such brutal attacks. Encryption based on the algorithms mentioned above are generally immune to these kinds of attack assuming that no backdoors exist in the programme. Calculations show that the period of time required to crack them through brute force is gigantic. This table will give an idea of the

dimensions.

2 to power of Approximates to

30 Age of planet earth (in years)

33 Probability of being killed by a lightning (per day)

61 Lifetime of universe in seconds

170 Amount of atoms on our planet

223 Amount of atoms in our galaxy

446 Amount of possible keys used by GUIDESX

2048 Amount of possible keys

The probability of being killed by a lightning is 2³³ to 1, this is about 8.5 billion to 1. Note: 128 bit keys generally provide maximum security. For most private and commercial applications 60 bit key length is sufficient. Only 56 bit and below keys can theoretically be broken by the "brute force" method.

To see how difficult this is let us look at estimates of the time required using brute force to break symmetric ciphers assuming that:

I. Every single computer (estimated at 3*108) on the earth is used full time.

ii. Every computer has the processing power of a PII 450Mhz. Then a single (3DES) key can be brute forced in an average of 457,351,814,728 years.

The table below shows how long the various types of keys remain secure for.

A number of assumptions are made:

i. The number of computers in the world is equal to 100 Billion (that's ten for every single person on earth in the year 2014 - there are expected to be 10 billion people alive in 2014).

ii. Each of the computers obey Moore's law (the power and speed of computers doubles approximately every 18 months) for the entire period of cracking. (NOTE: this assumption may break current theories on speed of light, quantum physics etc). In reality, Moore's Law is predicted to become infeasible within 10 years or so.

Cipher Effective Years until break
Key Size feasible with
500 10 100,000
Supercomputers Billion Deep Crack
computers machines
(PII 450)
3DES 112 61 44 45
CAST 128 85 65 69
IDEA 128 85 66 69