
grand cru (sifer)

cryptography mein, grand cru ack block sifer haye jiska aavishkaar 2000 mein johann borst dwara kiya gayaa thaa. ise nessie pariyojana koo prastut kiya gayaa thaa, lekin iska chayan naheen kiya gayaa thaa.
grand cru ack 10-round pratisthaapan-kramparivartan network haye joe kaafee hudd taka resundale (yaa aes) parr adharit haye. yeh pratyek operation key suraksha uddeshyon key anuroop, kaee resundale key unkeed operations koo pramukh-nirbhar sanchalanon key saath pratisthaapit kartaa haye. iska uddeshya cumm seey cumm resundale key roop mein surakshit aur shayed adhik surakshit ack sifer kaa utpaadan karna haye. block kaa aakar aur kunji kaa aakar donon 128 bits hain, aur pramukh anusuchi resundale key samaan haye.
grand cru koo "bahustariya suraksha" key siddhant parr design kiya gayaa haye. yeh swatantra kunjiyon key saath 4 upa-sanketikon kii ack shrinkhala key barabar haye, jaise kii yadi 3 kunjiyaan gyaat hain, tou shesh saanketik sanket abhee bhee surakshit honah chaahiye.