one-key cryptosystem

cryptology

Also known as: symmetric cryptosystem, symmetric encryption

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July 1, 2026

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Single-key cryptography, also known as symmetric cryptography, uses the same secret key for both encrypting and decrypting information. This method is efficient for securing communications but faces significant challenges, primarily the "key distribution problem".1

The key distribution problem arises because all participants must possess the identical secret key. Distributing this key securely, especially among geographically separated users, is difficult and often impractical for widespread use. Furthermore, as the number of users increases, the number of unique keys required grows exponentially, making management and security unfeasible for large groups.1

While single-key cryptography is effective for two parties, its limitations in key management make it less suitable for large, decentralized networks compared to asymmetric (two-key) cryptography.12

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public-key cryptography
Single-key cryptography is called symmetric for obvious reasons. A cryptosystem satisfying conditions 1–4 above is called asymmetric for equally obvious reasons. There are symmetric cryptosystems in which the encryption and decryption keys are not the same—for example, matrix transforms of the text in which one key is a nonsingular…
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Single-key cryptography is called symmetric for obvious reasons. A cryptosystem satisfying conditions 1–4 above is called asymmetric for equally obvious reasons. There are symmetric cryptosystems in which the encryption and decryption keys are not the same—for example, matrix transforms of the text in which one key is a nonsingular…
Read More

data encryption
Conventional symmetric encryption requires the same key for both encryption and decryption. A common symmetric encryption system is the Advanced Encryption Standard (AES), an extremely complex algorithm approved as a standard by the U.S. National Institute of Standards and Technology. Asymmetric encryption, or public-key cryptography, requires…
Read More
Conventional symmetric encryption requires the same key for both encryption and decryption. A common symmetric encryption system is the Advanced Encryption Standard (AES), an extremely complex algorithm approved as a standard by the U.S. National Institute of Standards and Technology. Asymmetric encryption, or public-key cryptography, requires…
Read More