A Darren Hardy 

A Michael F. Schwartz 

T Essence: A Resource Discovery System Based on Semantic File
Indexing 

J Proceedings of the USENIX Winter Conference 

C San Diego, California 

D January 1993 

P 361-374 

K RD, resource discovery 

X Available from
ftp:ftp.cs.colorado.edupubcstechreportsschwartzEssence.Conf.ps.Z
Or
ftp:ftp.cs.colorado.edupubcstechreportsschwartzEssence.Conf.txt.Z 

X A revised and extended journal version of this paper is
available as "Customized Information Extraction as a Basis for
Resource Discovery". 

X Note: the Essence prototype is available by anonymous FTP from
ftp.cs.colorado.edu, in the directory pubcsdistribsessence.  You
can also retrieve a WAIS "src" file for Essence in this
directory.  This will allow you to try Essence out. 

X Abstract: "Discovering different types of file resources (such
as documentation, programs, and images) in the vast amount of
data contained within network file systems is useful for both
users and system administrators.  In this paper we discuss the
\fIEssence\fP resource discovery system, which exploits file
semantics to index both textual and binary files.  By exploiting
semantics, Essence extracts keywords that summarize a file, and
generates a compact yet representative index. Essence nderstands
nested file structures (such as uuencoded, compressed, ``tar''
files), and recursively unravels such files to generate summaries
for them.  These features allow Essence to be used in a number of
useful settings, such as anonymous FTP archives. We present
measurements of our prototype and compare them to related
projects, such as the Wide Area Information Servers (WAIS) system
and the MIT Semantic File System (SFS). We demonstrate that
Essence can index more data types, generate sma ler indexes, and
in some casesndex data faster than these systems.  Our prototype
generates WAIS-compatible indexes, allowing WAIS users to take
advantage of the Essence indexing methods."