Reliability of URLs is currently subject to a number of single points of failure. As the number of users of the Web increases, and as the Web is increasingly used in mission-critical applications, it becomes clear that redundancy at all points is a requirement. With each level of indirection and redundancy comes the possibility of version skew, forgery, and corruption. Information providers and consumers should be able to select from a number of authentication mechanisms to balance between integrity, speed, and convenience. Engelbart also identified the need for a library system, including catalog numbers for documents.
Catalog numbers are a long-standing tradition in publishing and library science.
See W3C and Digital Libraries . We are developing extended fragment identifiers called XPointers for pointing into structured documents. As telephone and television are interfaced and integrated with desktop computers and the internet, addressing schemes for telephone numbers and TV channels will be necessary. Analogous to the way named anchors are addressed in HTML, mechanisms to address portions of audio and video data formats may be necessary. This is a publication history, or bibliography collected from IETF documents and W3C Technical Reports as well as a record of events.