Automatic Selection of Nearby Web Servers

John Heidemann and Vikram Visweswaraiah
USC/Information Sciences Institute

Abstract

Performance of global services such as the world-wide web can be improved by physically distributed replicas. Most replicated systems today request users to select manually a nearby replica (typically from a list of sites), yet users often are not willing or able to make an informed choice. This paper describes an approach to automatic replica selection which works without change to existing web clients and web and FTP servers. We describe the assumptions behind our approach and propose several metrics for estimation of network distance. We examine the feasibility behind this approach and compare the time required for replica-selection by each algorithm. Finally, we describe a small change to HTTP that would improve replica selection transparency.

Availability

This paper is available in several formats: abstract web page with pointers and cites, gzip'ed postscript, PDF, paper copies can be obtained by mail to the authors. Copyright terms for this paper appear below.

Reference

Heidemann98g

John Heidemann and Vikram Visweswaraiah. Automatic Selection of Nearby Web Servers. Technical Report 98-688, University of Southern California, December, 1998. <http://www.isi.edu/~johnh/PAPERS/Heidemann98g.html>.

@techreport{Heidemann98g,
	author = "John Heidemann and Vikram Visweswaraiah",
	title = "Automatic Selection of Nearby Web Servers",
	institution = "University of Southern California",
	year = "1998",
	number = "98-688",
	month = "December",
	keywords = "replica selection, http",
	url = "http://www.isi.edu/~johnh/PAPERS/Heidemann98g.html",
	psurl = "http://www.isi.edu/~johnh/PAPERS/Heidemann98g.ps.gz",
	pdfurl = "http://www.isi.edu/~johnh/PAPERS/Heidemann98g.pdf",
	otherurl = "ftp://usc.edu/pub/csinfo/tech-reports/papers/98-688.ps.Z",
	copyrightholder = "author",
	organization = "USC/Information Sciences Institute",
}

Copyright

This paper is copyright © 1998 by its authors. Permission to make digital or hard copies of part or all of this work for personal use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that new copies bear this notice and the full citation on the first page. Abstracting with credit is permitted.

To copy otherwise, to republish, to post on servers or to redistribute to lists, requires prior specific permission of the authors.