Calendaring Standards
There are numerous efforts to address the issue of federated free/busy, both at a standards level and through various product and service offerings. On the standards side, CalConnect has become the force of note in championing standards development. Netscape led the charge in 1996 with the formation of the Calendaring and Scheduling work group (CalSch) within the Internet Engineering Task Force (IETF). Although some critical work was completed within the IETF, other critical issues remained unresolved when the IETF disbanded the CalSch work group in 2004. "CalConnect was formed in large part to get the calendaring standards work moving again," reports Thewlis. "We are not a standards body, but our standardsrelated work is submitted into the IETF or other standards bodies as appropriate to help progress calendaring standards. We also do interoperability testing, and work both on improving existing standards, and proposing extensions or new standards in areas such as event publication and mobile calendaring."
CalConnect is known for two main pieces of work. First, for CalDAV- a calendaring and scheduling extension to the WebDAV standard. Second for its work on proposals into the IETF for simplification and rationalization of the existing base calendaring standards, being done under the auspices of the CALSIFY working group. With respect to the CalDAV work, it defines extensions critical to calendaring operations, such as search queries, access controls, sharing and synchronization. A number of current products incorporate CalDAV (e.g., the open-source Bedework, and Oracle's Calendar Server), and a number are in development (e.g., the Apple iCal Server in Apple's forthcoming Leopard Server, and the OSAF's Cosmo calendar server). The CalDAV technical committee at CalConnect focuses on developing use cases for calendar server interoperability, and documenting the customer requirements. Once the CalDAV work is complete, the next area of focus is real-time server-to-server interaction for free/busy lookups, a work effort that will be run out of the Real/Time technical committee.
There are currently 35 CalConnect members. Almost all are either calendaring vendors and developers, or large research universities. Only two are commercial organizations, a situation that Thewlis would like to change. "We really need additional commercial enterprises as members of CalConnect, because they bring a new and highly valued perspective on use cases, requirements and specifications," notes Thewlis.