Suppliers of Secure Computing SafeWord, a scheme based on hardware tokens. Includes rationale for single-use password systems, as well as other network security products.

Password tokens delivered on key fobs, palm pilots, hardware or software. Security for dial in, access control, internet and web connections. Offers a strong two factor system. Management software. Includes rationale and business case for token-based access.

Author of an Apple Newton OTP (S/Key) calculator. Site includes information about the author, and a link to his FTP site.

Provides primary or secondary authentication by regularly distributing passwords (or parts of passwords) through wireless phones. Time locked access.

Current specifications for the official internet standard (a continuation of the BellCore S/Key standard). Composition and membership information included.

A java applet OTP (S/Key) calculator. The applet downloads onto the client machine and calculates locally.

An OTP (S/Key) calculator for Nokia 9000 cellular phones. Includes S/Key information and resources.

otpCalc is an RFC2289 and RFC1760 compliant one time password calculator, written to use the GTK+ library for screen I/O.

OTP (S/Key) calculator for palm pilots. Site includes information about both source and binary distributions.

OTP (S/Key) client for the Palm platform. Includes screen captures, and general information as well as software downloads.

A simple Python library, currently under development, to generate OTP (S/Key) responses. RFC-2289 compliant. Includes links to development and release information.

A One-Time Password System. N. Haller, C. Metz, P. Nesser, et al. February 1998.

A technical description of the S/Key algorithm.

OTP (S/Key) calculator for MacOS X, MacOS X Server and NEXTSTEP. RFC-2289 compliant. Site includes software downloads, documentation and an introduction to the technology.

Scholarly paper by Neil Haller on the original S/Key system. Links to many citations from the original paper.