http://www.rfc-editor.org/rfc/rfc3874.txt
RFC 3874: A 224-bit One-way Hash Function: SHA-224, R. Housley2004-09-01T23:00:00-00:00This document specifies a 224-bit one-way hash function, called SHA-224. SHA-224 is based on SHA-256, but it uses a different initial value and the result is truncated to 224 bits. This memo provides information for the Internet community.