27,692 research outputs found
Rethinking Information Theory for Mobile Ad Hoc Networks
The subject of this paper is the long-standing open problem of developing a
general capacity theory for wireless networks, particularly a theory capable of
describing the fundamental performance limits of mobile ad hoc networks
(MANETs). A MANET is a peer-to-peer network with no pre-existing
infrastructure. MANETs are the most general wireless networks, with single-hop,
relay, interference, mesh, and star networks comprising special cases. The lack
of a MANET capacity theory has stunted the development and commercialization of
many types of wireless networks, including emergency, military, sensor, and
community mesh networks. Information theory, which has been vital for links and
centralized networks, has not been successfully applied to decentralized
wireless networks. Even if this was accomplished, for such a theory to truly
characterize the limits of deployed MANETs it must overcome three key
roadblocks. First, most current capacity results rely on the allowance of
unbounded delay and reliability. Second, spatial and timescale decompositions
have not yet been developed for optimally modeling the spatial and temporal
dynamics of wireless networks. Third, a useful network capacity theory must
integrate rather than ignore the important role of overhead messaging and
feedback. This paper describes some of the shifts in thinking that may be
needed to overcome these roadblocks and develop a more general theory that we
refer to as non-equilibrium information theory.Comment: Submitted to IEEE Communications Magazin
Source Delay in Mobile Ad Hoc Networks
Source delay, the time a packet experiences in its source node, serves as a
fundamental quantity for delay performance analysis in networks. However, the
source delay performance in highly dynamic mobile ad hoc networks (MANETs) is
still largely unknown by now. This paper studies the source delay in MANETs
based on a general packet dispatching scheme with dispatch limit (PD-
for short), where a same packet will be dispatched out up to times by its
source node such that packet dispatching process can be flexibly controlled
through a proper setting of . We first apply the Quasi-Birth-and-Death (QBD)
theory to develop a theoretical framework to capture the complex packet
dispatching process in PD- MANETs. With the help of the theoretical
framework, we then derive the cumulative distribution function as well as mean
and variance of the source delay in such networks. Finally, extensive
simulation and theoretical results are provided to validate our source delay
analysis and illustrate how source delay in MANETs are related to network
parameters.Comment: 11page
In Vivo Evaluation of the Secure Opportunistic Schemes Middleware using a Delay Tolerant Social Network
Over the past decade, online social networks (OSNs) such as Twitter and
Facebook have thrived and experienced rapid growth to over 1 billion users. A
major evolution would be to leverage the characteristics of OSNs to evaluate
the effectiveness of the many routing schemes developed by the research
community in real-world scenarios. In this paper, we showcase the Secure
Opportunistic Schemes (SOS) middleware which allows different routing schemes
to be easily implemented relieving the burden of security and connection
establishment. The feasibility of creating a delay tolerant social network is
demonstrated by using SOS to power AlleyOop Social, a secure delay tolerant
networking research platform that serves as a real-life mobile social
networking application for iOS devices. SOS and AlleyOop Social allow users to
interact, publish messages, and discover others that share common interests in
an intermittent network using Bluetooth, peer-to-peer WiFi, and infrastructure
WiFi.Comment: 6 pages, 4 figures, accepted in ICDCS 2017. arXiv admin note: text
overlap with arXiv:1702.0565
Analyzing Linear Communication Networks using the Ribosome Flow Model
The Ribosome Flow Model (RFM) describes the unidirectional movement of
interacting particles along a one-dimensional chain of sites. As a site becomes
fuller, the effective entry rate into this site decreases. The RFM has been
used to model and analyze mRNA translation, a biological process in which
ribosomes (the particles) move along the mRNA molecule (the chain), and decode
the genetic information into proteins.
Here we propose the RFM as an analytical framework for modeling and analyzing
linear communication networks. In this context, the moving particles are
data-packets, the chain of sites is a one dimensional set of ordered buffers,
and the decreasing entry rate to a fuller buffer represents a kind of
decentralized backpressure flow control. For an RFM with homogeneous link
capacities, we provide closed-form expressions for important network metrics
including the throughput and end-to-end delay. We use these results to analyze
the hop length and the transmission probability (in a contention access mode)
that minimize the end-to-end delay in a multihop linear network, and provide
closed-form expressions for the optimal parameter values
Spatial networks with wireless applications
Many networks have nodes located in physical space, with links more common
between closely spaced pairs of nodes. For example, the nodes could be wireless
devices and links communication channels in a wireless mesh network. We
describe recent work involving such networks, considering effects due to the
geometry (convex,non-convex, and fractal), node distribution,
distance-dependent link probability, mobility, directivity and interference.Comment: Review article- an amended version with a new title from the origina
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