Over the past several years, a number of information discovery and access tools have been introduced in the Internet, including Archie, Gopher, Netfind, and WAIS. These tools have become quite popular, and are helping to redefine how people think about wide-area network applications. Yet, they are not well suited to supporting the future information infrastructure, which will be characterized by enormous data volume, rapid growth in the user base, and burgeoning data diversity. In this paper we indicate trends in these three dimensions and survey problems these trends will create for current approaches. We then suggest several promising directions of future resource discovery research, along with some initial results from projects carried out by members of the Internet Research Task Force Research Group on Resource Discovery and Directory Service.

Nebula is a file system that explicitly supports information management. It differs from traditional systems in three important ways. First, Nebula implements files as sets of attributes. Each attribute describes some property of the file such as owner, protection, functions defined, sections specified, project, or file type. The content of the file is represented by a special text attribute. Second, Nebula supports associative access of files within a scoped index. A scoped index restricts associative access to a subset of the files in one or more file systems. Finally, Nebula replaces traditional directories with database views. A directory implements a naming closure; i.e. the name of a file is assigned by the directories in which it resides. A view is a query that selects file objects from a scoped index. Thus, the name of a file is a property of the file, not the view. Like directories, views can be named and included in other views. When a file (or view) is created, it is placed ...

Access to information using the Internet has undergone dramatic change and expansion recently. The unrivaled success of the World Wide Web has altered the Internet from something approachable only by the initiated to something of a media craze -- the information superhighway made manifest in the personal `home page.' This paper surveys the beginnings of network information discovery and retrieval, how the Web has created a surprising level of integration of these systems, and where the current state of the art lies in creating globally accessible information spaces and supporting access to those information spaces. * This work was supported in part by NASA as part of the Repository Based Software Engineering project, cooperative agreement NCC-9-16. 2 1 -- Introduction In a previous survey [15], I addressed repository services in support of software development. This paper reexamines some of those services in the more general context of information retrieval and examines a number o...