Acronym: Secure Remote Password
From the home page:
- The Project's primary purpose is to improve password security by making strong password authentication technology a standard part of deployed real-world systems. This is accomplished by making this technology an easy-to-use, hassle-free alternative to weak and vulnerable legacy password authentication schemes. SRP makes these objectives possible because it offers a unique combination of password security, user convenience, and freedom from restrictive licenses. ...more
Available under a "BSD-style license."