A Ruby gem for simplifying random password generation, password strength testing, password hashing and salting, and password-hash authentication.

A Chef cookbook cookbook to download files over HTTPS using TLS client certificate authentication.

Rack middleware for authentication using JSON Web Tokens using the jwt_claims and json_web_token gems.

A modular implementation of Rack Auth

rack-auth-ldap : provide LDAP authentication for Rack middelware

JWT-based token authentication middleware for Rack.

OAuth Echo authentication by a rack middleware

Rack Middleware for OAuth Authorization and Authentication via/twitter

SimpleAuth HMAC authentication

Rack webmoney authentication

Simple HTTP proxy which adds Conjur authentication headers

Rack authentication middleware

Simple Google authentication.

Ruby PAM (Pluggable Authentication Modules) integration

Plugin that adds token authentication methods to Roda

Ruby Role-Based Authentication

Rubius provides a simple interface to RADIUS authentication

Simple RSS parser that supports feeds with HTTP Basic Authentication

Token based authentication

Net::Tofu is a client and certificate pinning library for Geminispace, derived from the 'trust on first use' authentication scheme (https://en.wikipedia.org/wiki/Trust_on_first_use).