all current DAAP clients (including official iTunes before iTunes 7.0) will fail to connect to an iTunes 7.0 server, receiving a '403 Forbidden' HTTP error. The iTunes 7.0 authentication traffic analysis seem to indicate that a certificate exchange is performed to calculate the hash sent in the 'Client-DAAP-Validation' header. This authentication has not yet been reverse engineered. DAAP clients DAAP servers See also List of software using Digital Audio Access Protocol Digital Audio Control Protocol Remote Audio Output Protocol Notes and references Apple Inc. services ITunes Data transmission Network protocols Computer-related introductions in 2003