In the context of an HTTP transaction, basic access authentication is a method for an HTTP user agent (e.g. a web browser) to provide a user name and password when making a request. In basic HTTP authentication, a request contains a header field in the form of Authorization: Basic , where credentials is the Base64 encoding of ID and password joined by a single colon :. It was originally implemented by Ari Luotonen at CERN in 1993 and defined in the HTTP 1.0 specification in 1996. It is specified in RFC 7617 from 2015, which obsoletes RFC 2617 from 1999.