NULL algorithm

The NULL algorithm is an algorithm that does nothing. It appears as a scientific joke in computer science, among other things, in RFC 2410 as an alleged block cipher and alternative to the Caesar cipher . Beyond its joking origin, the term is also used to indicate that certain program code - consciously or due to errors - does nothing or does nothing.

The algorithm is to RFC 2410 when using According IPsec with ESP for authentication and integrity without confidentiality worry. The NULL algorithm allows you to specify that encryption does not apply. This is known as "ESP-ZERO".

Various advantages are attested to the algorithm, such as high flexibility or performance . Since the NULL algorithm does nothing, it is faster than other symmetric encryption algorithms . It can be used with any hardware and operating system platform.

The origin is jokingly assumed in Roman times. However, since there was no numeral for the zero in ancient Rome , written records of the development of the algorithm have been lost.

definition

NULL defines the mathematical use of the identity function I applied to a block of data b :

NULL(b) = I(b) = b

example

Daten      = "Network Security People Have A Strange Sense Of Humor"
Datenlänge = 53
NULL_Daten = "Network Security People Have A Strange Sense Of Humor"

Like other modern cipher schemes, the NULL algorithm can use keys of varying lengths. However, longer keys do not improve security.

The company IBM provides the program IEFBR14 under the operating system z / OS , which in fact fulfills no function, but is useful nonetheless.

Web links

• RFC 2410 - "The NULL Encryption Algorithm and Its Use With IPsec"