Editing RC5 (section)

{{Short description|Block cipher}}
{{About|the block cipher|the infrared remote control protocol|RC-5}}
{{Infobox block cipher
| name          = RC5
| image         = [[Image:RC5 InfoBox Diagram.svg|160px|center]]
| caption       = One round (two half-rounds) of the RC5 block cipher
| designers     = [[Ron Rivest]]
| publish date  = 1994
| derived from  = 
| derived to    = [[RC6]], [[Akelarre (cipher)|Akelarre]]
| key size      = 0 to 2040 bits (128 suggested)
| block size    = 32, 64 or 128 bits (64 suggested)
| structure     = [[Feistel cipher|Feistel]]-like network
| rounds        = 1-255 (12 suggested originally)
| cryptanalysis = 12-round RC5 (with 64-bit blocks) is susceptible to a [[differential cryptanalysis|differential attack]] using 2<sup>44</sup> chosen plaintexts.<ref name="Biryukov"/>
}}
In [[cryptography]], '''RC5''' is a [[Symmetric-key algorithm|symmetric-key]] [[block cipher]] notable for its simplicity. Designed by [[Ron Rivest|Ronald Rivest]] in 1994,<ref name="fse1994">{{cite conference|last=Rivest|first=R. L.|year=1994|title=The RC5 Encryption Algorithm|book-title=Proceedings of the Second International Workshop on Fast Software Encryption (FSE) 1994e|pages=86&ndash;96|url=http://theory.lcs.mit.edu/~rivest/Rivest-rc5rev.pdf|access-date=2004-12-18|archive-date=2007-04-17|archive-url=https://web.archive.org/web/20070417135716/http://theory.lcs.mit.edu/~rivest/Rivest-rc5rev.pdf|url-status=dead}}</ref> ''RC'' stands for "Rivest Cipher", or alternatively, "Ron's Code" (compare [[RC2]] and [[RC4 (cipher)|RC4]]). The [[Advanced Encryption Standard]] (AES) candidate [[RC6]] was based on RC5.