Check out the new USENIX Web site.

USENIX Home . About USENIX . Events . membership . Publications . Students
3rd International Conference on Mobile Systems, Applications, and Services — Abstract

Pp. 93–106 of the Proceedings

DeltaCast: Efficient File Reconciliation in Wireless Broadcast Systems

Julian Chesterfield, University of Cambridge, and Pablo Rodriguez, Microsoft Research

Abstract

Recently, there has been an increasing interest in wireless broadcast systems as a means to enable scalable content delivery to large numbers of mobile users. However, gracefully providing efficient reconciliation of different versions of a file over such broadcast channels still remains a challenge. Such systems often lack a feedback channel and consequently updates cannot be easily tailored to a specific user. Moreover, given the potentially large number of possible versions of a file, it is impractical to send a tailored update for each particular user.

In this paper we consider the problem of efficiently updating files in such wireless broadcast channels. To this extent, we present DeltaCast, a system that combines hierarchical hashes and erasure codes to minimise the amount of battery power and the amount of time needed to synchronise each mobile device. Based on our experimental results, we show that DeltaCast is able to efficiently identify the missing portions of a file and quickly updated each client.

  • View the full text of this paper in HTML and PDF.
    Click here if you have forgotten your password Until June 2006, you will need your USENIX membership identification in order to access the full papers. The Proceedings are published as a collective work, © 2005 by the USENIX Association. All Rights Reserved. Rights to individual papers remain with the author or the author's employer. Permission is granted for the noncommercial reproduction of the complete work for educational or research purposes. USENIX acknowledges all trademarks within this paper.

  • If you need the latest Adobe Acrobat Reader, you can download it from Adobe's site.
To become a USENIX Member, please see our Membership Information.

?Need help? Use our Contacts page.

Last changed: 24 May 2005 aw
Technical Program
MobiSys '05 Home
USENIX home