RSA algoritam i njegova praktična primena / RSA algorithm

• Main Author: Sonja R. Kuljanski
• Format: Article
• Language: English
• Published: University of Defence in Belgrade 2010-07-01
• Series: Vojnotehnički Glasnik
• Subjects: kriptografija; enkripcija; dekripcija; RSA; PKCS; OAEP; SAEP; cryptography; encryption; decryption
• Online Access: http://scindeks.ceon.rs/Article.aspx?artid=0042-84691003065K

RSA algoritam jeste algoritam sa javnim ključem koji uključuje tri koraka: generisanje ključa, enkripciju i dekripciju. RSA enkripciona šema je determinističaka što znači da se osnovni tekst uvek enkriptuje u isti šifrovani tekst za unapred zadati javni ključ. Da bi se izbegao ovaj problem, praktična implementacija RSA algoritma obično koristi neke strukture, kao što je dodavanje slučajnog teksta u samu poruku pre enkripcije. Ovo dodavanje obezbeđuje da osnovna poruka bude sigurna i da se može enkriptovati u veliki broj različitih šifrovanih poruka. Standardi, kao što je PKCS #1, pažljivo su dizajnirani tako da dodaju tekst u osnovnu poruku pre RSA same enkripcije. / RSA is an algorithm for public-key encryption. It is the first algorithm known to be suitable for encryption as well as digital signing. The RSA encryption scheme is deterministic in the sense that under a fixed public key, a particular plaintext is always encrypted to the same ciphertext. A deterministic encryption scheme (as opposed to a probabilistic encryption scheme) is a cryptosystem which always produces the same ciphertext for a given plaintext and key, even over separate executions of the encryption algorithm. Probabilistic encryption uses randomness in an encryption algorithm, so that when encrypting the same message several times it will, in general, yield different ciphertexts.