telecommunication Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than tha ...

, a

password A password, sometimes called a passcode (for example in Apple devices), is secret data, typically a string of characters, usually used to confirm a user's identity. Traditionally, passwords were expected to be memorized, but the large number of ...

length parameter is a basic parameter the value of which affects password strength against

brute force attack In cryptography, a brute-force attack consists of an attacker submitting many passwords or passphrases with the hope of eventually guessing correctly. The attacker systematically checks all possible passwords and passphrases until the corr ...

and so is a contributor to

computer security Computer security, cybersecurity (cyber security), or information technology security (IT security) is the protection of computer systems and networks from attack by malicious actors that may result in unauthorized information disclosure, t ...

. One use of the password length parameters is in the expression

P = L\times R /S

, where

P

is the probability that a password can be guessed in its lifetime,

L

is the maximum lifetime a password can be used to log into a system,

R

is the number of guesses per unit of

time Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, t ...

, and

S

is the number of unique algorithm-generated passwords (the 'password space'). The degree of password security is determined by the probability that a password can be guessed in its lifetime.

References

Computer network security Password authentication {{computer-security-stub

See also

References