The learning curve for security is severe and unforgiving. Specifications promise infinite flexibility, habitually give old concepts new names, are riddled with extensions, and almost seem designed to deliberately confuse. For a back-end REST developer, choking all this down for the first time is mission impossible. With an aggressive distaste for fancy terminology, this session delves into OAuth 2.0 as it pertains to REST and shows how it falls into two camps: stateful and stateless. The presentation also details a competing Amazon-style approach called HTTP Signatures and digs into the architectural differences of all three, with a heavy focus on the wire, showing actual HTTP messages and enough detail to have you thinking, “I could write this myself.”