This memo specifies an Authentication and Key Agreement (AKA) based one-time password generation mechanism for Hypertext Transfer Protocol (HTTP) Digest access authentication. The HTTP Authentication Framework includes two authentication schemes: Basic and Digest. Both schemes employ a shared secret based mechanism for access authentication. The AKA mechanism performs user authentication and session key distribution in Universal Mobile Telecommunications System (UMTS) networks. AKA is a challenge- response based mechanism that uses symmetric cryptography.