Internet-based vehicular ad hoc network (Ivanet) is an emerging technique that combines a wired Internet and a vehicular ad hoc network (Vanet) for developing an ubiquitous communication infrastructure and improving universal information and service accessibility. A key design optimization technique in Ivanets is to cache the frequently accessed data items in a local storage of vehicles. Since vehicles are not critically limited by the storage/memory space and power consumption, selecting proper data items for caching is not very critical. Rather, an important design issue is how to keep the cached copies valid when the original data items are updated. This is essential to provide fast access to valid data for fast moving vehicles. In this paper, we propose a cooperative cache invalidation (CCI) scheme and its enhancement (ECCI) that take advantage of the underlying location management scheme to reduce the number of broadcast operations and the corresponding query delay. We develop an analytical model for CCI and ECCI techniques for fasthand estimate of performance trends and critical design parameters. Then, we modify two prior cache invalidation techniques to work in Ivanets: a poll-each-read (PER) scheme, and an extended asynchronous (EAS) scheme. We compare the performance of four cache invalidation schemes as a function of query interval, cache update interval, and data size through extensive simulation. Our simulation results indicate that the proposed schemes can reduce the query delay up to 69% and increase the cache hit rate up to 57%, and have the lowest communication overhead compared to the prior PER and EAS schemes.
Article
Cache Invalidation Strategies for Internet-based Vehicular Ad Hoc Networks
Computer Communications
Document Type
Article
Publication Date
2-1-2012
Abstract
DOI
10.1016/j.comcom.2011.10.013
Version
Postprint
Publisher's Statement
NOTICE: this is the author’s version of a work that was accepted for publication in Computer Communications. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Computer Communications, 35, 3, (02-01-2012); 10.1016/j.comcom.2011.10.013
Citation Information
S. Lim, C. Yu and C. R. Das, "Cache invalidation strategies for Internet-based vehicular ad hoc networks," Comput. Commun., vol. 35, pp. 380-391, 2012.
This research was supported in part by Startup Grant in Dept. of
Computer Science at Texas Tech University and US National
Science Foundation (NSF) under the Grants CNS-0831673,
CNS-1004210, and CNS-0831853, and Korea National Research
Foundation (NRF) WCU Grant R31-2008-000-10100-0. This work
was published in part at the 18th International Conference on
Computer Communications and Networks (ICCCN) 2009 [40].