(Georgia Institute of Technology, 2006)
Zhao, Wenrui; Chen, Yang; Ammar, Mostafa H.; Corner, Mark D.; Levine, Brian; Zegura, Ellen W.
Delay tolerant networks (DTNs) are a class of
emerging networks that are subject to frequent and long-duration
partitions. Due to intermittent connectivity, DTNs might
be significantly limited in supporting application needs, for
example, leading to low throughput or high delay. To address
this problem, we propose the use of throw-boxes to improve
data delivery performance. Throw-boxes are small, inexpensive
devices equipped with wireless interfaces and deployed to relay
data between mobile nodes. Being small and inexpensive, throwboxes
represent a flexible and cost-effective approach to enhance
network capacity.
In this paper, we systematically study two inter-related issues,
namely deployment and routing, in using throw-boxes for
throughput enhancement. Specifically, we develop algorithms
for throw-box deployment and data forwarding under various
routing strategies, including single path, multi-path and epidemic
routing. Using extensive ns simulations, we evaluate the utility of
throw-boxes and the impact of various routing and deployment
strategies on network performance. Our objective is to guide
the design and operations of throw-box-enhanced DTNs. We
find that throw-boxes are very effective in improving both data
delivery ratio and delay, especially for multi-path routing and
environments with regular node movement.