Little research has been performed directly on large-scale autonomous replication; only in the past few years have researchers begun assembling such systems [5]. There has, however, been a great deal of research on the various components of such a system, such as data caching and resource location. We anticipate that the next few years will witness a convergence among distributed systems researchers toward large-scale autonomous replication as large-scale systems such as the World Wide Web become more ubiquitous. Traditional client caching for example has slowly been giving way to more aggressive types of client caching, and recent consistency research has focused on increasingly sophisticated ways to update caches.
This chapter discusses current research into the various fields that
have inspired large-scale autonomous replication.
Section 
discusses distributed file
systems, and section discusses recent results of
earlier distributed file system research.
Section reviews current research on
invalidation protocols, essential to any wide-area caching scheme,
and section
covers research into locating nearby Internet resources of interest.
Finally, section discusses recent Internet
surveys. We include a description of group-communication research in
Appendix . This research does not
directly apply to the work performed for this thesis, but is necessary
for efficiently maintaining a large, shared databases such as that
used by the registry.