Secure Hash Algorithm 1

Why Trust Techopedia

What Does Secure Hash Algorithm 1 Mean?

The Secure Hash Algorithm 1 (SHA-1) is a cryptographic computer security algorithm. It was created by the US National Security Agency in 1995, after the SHA-0 algorithm in 1993, and it is part of the Digital Signature Algorithm or the Digital Signature Standard (DSS).


Techopedia Explains Secure Hash Algorithm 1

SHA-1 produces a 160-bit hash value or message digests from the inputted data (data that requires encryption), which resembles the hash value of the MD5 algorithm. It uses 80 rounds of cryptographic operations to encrypt and secure a data object. Some of the protocols that use SHA-1 include:

  • Transport Layer Security (TLS)
  • Secure Sockets Layer (SSL)
  • Pretty Good Privacy (PGP)
  • Secure Shell (SSH)
  • Secure/Multipurpose Internet Mail Extensions (S/MIME)
  • Internet Protocol Security (IPSec)

SHA-1 is commonly used in cryptographic applications and environments where the need for data integrity is high. It is also used to index hash functions and identify data corruption and checksum errors.


Related Terms

Margaret Rouse
Senior Editor
Margaret Rouse
Senior Editor

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.