IDEA (International Data Encryption Algorithm) is an encryption algorithm developed at ETH in Zurich, Switzerland. It uses a block cipher with a bit key, and is generally considered to be very secure. RSA's FAQ on Cryptography mentions IDEA among several block ciphers. International Data Encryption Algorithm (IDEA) is a block cipher designed by Xuejia Lai and James L. Massey of ETH-Zürich and was first described in The International Data Encryption Algorithm (IDEA) is a symmetric-key, block cipher. It was published in by Lai, Massey, and Murphy [3]. The new algorithm was called the Improved Proposed Encryption Standard (IPES); its name changed to IDEA in IDEA is a candidate block cipher to the NESSIE Project.

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Multiplication, as used in IDEA, requires some explanation.

Multiplication by zero always produces zero, and is not invertible. Multiplication modulo n is also not invertible whenever it is by a number which is not relatively prime to n. The way multiplication is used idea algorithm in cryptography IDEA, it is necessary that it be always invertible.

This is true of multiplication IDEA style.

## What is International Data Encryption Algorithm (IDEA)? - Definition from

Thus, if one forms a multiplication table for the numbers from 1 through 65, each row and column will idea algorithm in cryptography every number once only, forming a Latin square, and providing idea algorithm in cryptography invertible operation.

The numbers that 16 bits normally represent are from 0 to 65, or, perhaps even more commonly, fromto 32, In IDEA, for purposes of multiplication, a 16 bit word containing all zeroes is considered to represent the number 65,; other numbers are represented in conventional unsigned notation, and multiplication is modulo the prime number 65, Before round 1, or as the first part of it, the following is done: Multiply A by K 1.

Multiply D by K 4. Round 1 proper consists of the following: Multiply E by K 5.

## INTERNATIONAL DATA ENCRYPTION ALGORITHM (IDEA) – A TYPICAL ILLUSTRATION | Open Access Journals

Add the new value of E to F. Multiply the new value of F by K 6. This type of cryptography ensures only confidentiality and fails to provide the other objectives of cryptography. Even more importantly the disadvantage of symmetric key cryptography is that it cannot idea algorithm in cryptography large communication networks[2].

If a node in a communication network of n nodes needs to communicate confidentially with all other nodes in the network, it needs n - 1 shared secrets. For large value of n this is highly impractical and inconvenient.

On the other hand, an advantage over public key cryptosystems is that symmetric cryptosystems require much smaller key sizes for the same level of security[1].

Hence, the computations are much faster and the idea algorithm in cryptography requirements are smaller Whitfield et al, In public key cryptosystems there are two different keys: If data is encrypted with a public key, it can only be decrypted using the corresponding private key, and vice versa[3].

### INTERNATIONAL DATA ENCRYPTION ALGORITHM (IDEA) â A TYPICAL ILLUSTRATION

Today, all public key cryptosystems rely on some computationally intractable problems. For example, the cryptosystem RSA relies on the difficulty of factoring large integers, while El-Gamal cryptosystem relies on the discrete logarithm problem DLPwhich is the problem of finding a logarithm of a idea algorithm in cryptography element with generator base in a finite Abelian group Public key cryptosystems do not need to have a shared secret between communicating parties.

This solves the problem of large confidential communication network introduced earlier. In addition, public key cryptography opened door for ways of implementing technologies to ensure all goals of cryptography.