[1] Authors listed alphabetically. Contact author: Michael Wellman, Department of EECS. Other project members contributing to the work described herein include Ken Alexander, Gene Alloway, Karen Drabenstott, Randall Frank, Olivia Frost, George Furnas, Daniel Kiskis, Wendy Lougee, Jeffrey MacKie-Mason, Greg Peters, John Price-Wilkin, and Amy Warner. This work was supported by the NSF/ARPA/NASA Digital Library initiative. Further information is available at http://http2.sils.umich.edu/UMDL/HomePage.html.

[2] This avoids the need to negotiate with the registry, which can lead to deadlock since the registry contains the information about which agents can facilitate the negotiation process.

[3] Input parameters are denoted by an asterisk before the variable identifier, output parameters by asterisk after.

[4] We are implementing the distributed registry using commercial database technology. Our intent is to use replication servers to support a powerful distributed search paradigm, that while robust and scalable, is transparent to the rest of the UMDL system.