Computer Laboratory

Technical reports

Block encryption

D. Wheeler

November 1987, 4 pages


A fast and simple way of encrypting computer data is needed. The UNIX crypt is a good way of doing this although the method is not cryptographically sound for text. The method suggested here is applied to larger blocks than the DES method which uses 64 bit blocks, so that the speed of encyphering is reasonable. The algorithm is designed for software rather than hardware. This forgoes two advantages of the crypt algorithm, namely that each character can be encoded and decoded independently of other characters and that the identical process is used both for encryption and decryption. However this method is better for coding blocks directly.

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BibTeX record

  author =	 {Wheeler, D.},
  title = 	 {{Block encryption}},
  year = 	 1987,
  month = 	 nov,
  url = 	 {},
  institution =  {University of Cambridge, Computer Laboratory},
  number = 	 {UCAM-CL-TR-120}