What does "decoding" mean in computer terms?

In computers, "decoding" refers to the process of recovering the plaintext information hidden in the ciphertext without knowing the key. In the process of computer network transmission, in addition to legal recipients, there are also unauthorized persons who intercept information during the information transmission process through various methods; therefore, confidential information is usually encrypted when transmitted over the network, but sometimes it is It can be intercepted by unauthorized users, and the plain text or even the key can be obtained through password deciphering, causing secrets to be leaked.

The operating environment of this tutorial: Windows 7 system, Dell G3 computer.

The computer term "decryption" refers to the process of recovering the plaintext information hidden in the ciphertext without knowing the key.

Password deciphering is also an attack on the cryptographic system. Successful password cracking can recover plaintext or keys, and can also discover weaknesses in the cryptographic system. Crypto-cracking technology refers to various technologies, means, measures, methods and tools commonly used in the process of crypto-cracking.

In the process of computer network transmission, in addition to legal recipients, there are also unauthorized persons. Unauthorized persons use various methods to intercept information during the information transmission process. Therefore, confidential information is usually encrypted when transmitted over the network, but sometimes it can still be intercepted by unauthorized users, and the plaintext or even the key can be obtained through password deciphering, causing the confidentiality to be leaked.

The main factors of "decoding" computer terminology:

1. The strength of the algorithm

For example, information cannot be decrypted by anything short of trying all possible key combinations.

2. Confidentiality of the key

The degree of confidentiality of the data is directly related to the degree of confidentiality of the key. Pay attention to the distinction between the key and the algorithm. The algorithm does not need to be kept confidential. The encrypted data is first used with a key and then passed through the encryption algorithm.

3. Key length

The length of the key is in "bits". According to the encryption and decryption application, add to the length of the key. One bit is equivalent to doubling the total number of possible keys.

Simply put, the number of possible combinations of bits that constitute a key of any given length can be expressed as 2 to the nth power, where n is a key length.

So the recipe for a 40-bit key length would be 2 to the 40th power, or a trillion possible different keys, in stark contrast to the speed of modern computers.

Password cracking method

Password cracking methods are divided into ciphertext attack method and known plaintext attack method.

The ciphertext attack method starts with analyzing the ciphertext, judging and verifying the encryption system and key, and then deciphering the plaintext.

The known plaintext attack method uses a certain number of correspondences between ciphertext and plaintext that have been mastered to analyze and verify the encryption system and key, and then decipher other plaintexts.

Deciphering passwords of different strengths has different requirements for decoding conditions, and the degree of difficulty is also very different.

Cryptocracking requires codebreakers to have a solid theoretical foundation in coding and deciphering, rich practical experience, extensive knowledge of related disciplines, rigorous logical reasoning abilities and a tenacious work spirit.

With the widespread use of computers and related technical equipment, cryptography theory and technology will continue to develop. Code deciphering will be highly valued by countries around the world.

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