622 research outputs found
PROTECT: Proximity-based Trust-advisor using Encounters for Mobile Societies
Many interactions between network users rely on trust, which is becoming
particularly important given the security breaches in the Internet today. These
problems are further exacerbated by the dynamics in wireless mobile networks.
In this paper we address the issue of trust advisory and establishment in
mobile networks, with application to ad hoc networks, including DTNs. We
utilize encounters in mobile societies in novel ways, noticing that mobility
provides opportunities to build proximity, location and similarity based trust.
Four new trust advisor filters are introduced - including encounter frequency,
duration, behavior vectors and behavior matrices - and evaluated over an
extensive set of real-world traces collected from a major university. Two sets
of statistical analyses are performed; the first examines the underlying
encounter relationships in mobile societies, and the second evaluates DTN
routing in mobile peer-to-peer networks using trust and selfishness models. We
find that for the analyzed trace, trust filters are stable in terms of growth
with time (3 filters have close to 90% overlap of users over a period of 9
weeks) and the results produced by different filters are noticeably different.
In our analysis for trust and selfishness model, our trust filters largely undo
the effect of selfishness on the unreachability in a network. Thus improving
the connectivity in a network with selfish nodes.
We hope that our initial promising results open the door for further research
on proximity-based trust
Intertwined localization and error-resilient geographic routing for mobile wireless sensor networks
“This is a post-peer-review, pre-copyedit version of an article published in Wireless Networks. The final authenticated version is available online at: http://dx.doi.org/10.1007/s11276-018-1836-7”Geographic routing in wireless sensor networks brings numerous inherent advantages, albeit its performance relying heavily on accurate node locations. In mobile networks, localization of the continuously moving nodes is a challenging task and location errors are inevitable and affect considerably routing decisions. Our proposal is in response to the unrealistic assumption widely made by previous geographic routing protocols that the accurate location of mobile nodes can be obtained at any time. Such idealized assumption results in under-performing or infeasible routing protocols for the real world applications. In this paper, we propose INTEGER, a localization method intertwined with a new location-error-resilient geographic routing specifically designed for mobile sensor networks even when these networks are intermittently connected. By combining the localization phase with the geographic routing process, INTEGER can select a relay node based on nodes’ mobility predictions from the localization phase. Results show that INTEGER improves the efficiency of the routing by increasing the packet delivery ratio and by reducing the energy consumption while minimizing the number of relay nodes compared to six prevalent protocols from the literature.Peer ReviewedPostprint (author's final draft
A Taxonomy on Misbehaving Nodes in Delay Tolerant Networks
Delay Tolerant Networks (DTNs) are type of Intermittently Connected Networks (ICNs) featured by long delay, intermittent connectivity, asymmetric data rates and high error rates. DTNs have been primarily developed for InterPlanetary Networks (IPNs), however, have shown promising potential in challenged networks i.e. DakNet, ZebraNet, KioskNet and WiderNet. Due to unique nature of intermittent connectivity and long delay, DTNs face challenges in routing, key management, privacy, fragmentation and misbehaving nodes. Here, misbehaving nodes i.e. malicious and selfish nodes launch various attacks including flood, packet drop and fake packets attack, inevitably overuse scarce resources (e.g., buffer and bandwidth) in DTNs. The focus of this survey is on a review of misbehaving node attacks, and detection algorithms. We firstly classify various of attacks depending on the type of misbehaving nodes. Then, detection algorithms for these misbehaving nodes are categorized depending on preventive and detective based features. The panoramic view on misbehaving nodes and detection algorithms are further analyzed, evaluated mathematically through a number of performance metrics. Future directions guiding this topic are also presented
Recommended from our members
Spreadable Connected Autonomic Networks (SCAN)
A Spreadable Connected Autonomic Network (SCAN) is a mobile network that automatically maintains its own connectivity as nodes move. We envision SCANs to enable a diverse set of applications such as self-spreading mesh networks and robotic search and rescue systems. This paper describes our experiences developing a prototype robotic SCAN built from commercial, off-the-shelf hardware, to support such applications. A major contribution of our work is the development of a protocol, called SCAN1, which maintains network connectivity by enabling individual nodes to determine when they must constrain their mobility in order to avoid disconnecting the network. SCAN1 achieves its goal through an entirely distributed process in which individual nodes utilize only local (2-hop) knowledge of the network's topology to periodically make a simple decision: move, or freeze in place. Along with experimental results from our hardware testbed, we model SCAN1's performance, providing both supporting analysis and simulation for the efficacy of SCAN1 as a solution to enable SCANs. While our evaluation of SCAN1 in this paper is limited to systems whose capabilities match those of our testbed, SCAN1 can be utilized in conjunction with a wide-range of potential applications and environments, as either a primary or backup connectivity maintenance mechanism
Resource-efficient strategies for mobile ad-hoc networking
The ubiquity and widespread availability of wireless mobile devices with ever increasing
inter-connectivity (e. g. by means of Bluetooth, WiFi or UWB) have led to new and emerging
next generation mobile communication paradigms, such as the Mobile Ad-hoc NETworks
(MANETs). MANETs are differentiated from traditional mobile systems by their unique properties,
e. g. unpredictable nodal location, unstable topology and multi-hop packet relay. The
success of on-going research in communications involving MANETs has encouraged their applications
in areas with stringent performance requirements such as the e-healthcare, e. g. to
connect them with existing systems to deliver e-healthcare services anytime anywhere. However,
given that the capacity of mobile devices is restricted by their resource constraints (e. g.
computing power, energy supply and bandwidth), a fundamental challenge in MANETs is how
to realize the crucial performance/Quality of Service (QoS) expectations of communications in
a network of high dynamism without overusing the limited resources.
A variety of networking technologies (e. g. routing, mobility estimation and connectivity
prediction) have been developed to overcome the topological instability and unpredictability
and to enable communications in MANETs with satisfactory performance or QoS. However,
these technologies often feature a high consumption of power and/or bandwidth, which makes
them unsuitable for resource constrained handheld or embedded mobile devices. In particular,
existing strategies of routing and mobility characterization are shown to achieve fairly
good performance but at the expense of excessive traffic overhead or energy consumption. For
instance, existing hybrid routing protocols in dense MANETs are based in two-dimensional organizations
that produce heavy proactive traffic. In sparse MANETs, existing packet delivery
strategy often replicates too many copies of a packet for a QoS target. In addition, existing
tools for measuring nodal mobility are based on either the GPS or GPS-free positioning systems,
which incur intensive communications/computations that are costly for battery-powered
terminals. There is a need to develop economical networking strategies (in terms of resource
utilization) in delivering the desired performance/soft QoS targets.
The main goal of this project is to develop new networking strategies (in particular, for
routing and mobility characterization) that are efficient in terms of resource consumptions while
being effective in realizing performance expectations for communication services (e. g. in the
scenario of e-healthcare emergency) with critical QoS requirements in resource-constrained
MANETs.
The main contributions of the thesis are threefold:
(1) In order to tackle the inefficient bandwidth utilization of hybrid service/routing discovery
in dense MANETs, a novel "track-based" scheme is developed. The scheme deploys
a one-dimensional track-like structure for hybrid routing and service discovery. In comparison
with existing hybrid routing/service discovery protocols that are based on two-dimensional
structures, the track-based scheme is more efficient in terms of traffic overhead (e. g. about 60%
less in low mobility scenarios as shown in Fig. 3.4). Due to the way "provocative tracks" are
established, the scheme has also the capability to adapt to the network traffic and mobility for
a better performance.
(2) To minimize the resource utilization of packet delivery in sparse MANETs where wireless
links are intermittently connected, a store-and-forward based scheme, "adaptive multicopy
routing", was developed for packet delivery in sparse mobile ad-hoc networks. Instead
of relying on the source to control the delivery overhead as in the conventional multi-copy
protocols, the scheme allows each intermediate node to independently decide whether to forward
a packet according to the soft QoS target and local network conditions. Therefore, the
scheme can adapt to varying networking situations that cannot be anticipated in conventional
source-defined strategies and deliver packets for a specific QoS targets using minimum traffic
overhead.
ii
(3) The important issue of mobility measurement that imposes heavy communication/computation
burdens on a mobile is addressed with a set of resource-efficient "GPS-free" soluti ons,
which provide mobility characterization with minimal resource utilization for ranging and signalling
by making use of the information of the time-varying ranges between neighbouring
mobile nodes (or groups of mobile nodes). The range-based solutions for mobility characterization
consist of a new mobility metric for network-wide performance measurement, two
velocity estimators for approximating the inter-node relative speeds, and a new scheme for
characterizing the nodal mobility. The new metric and its variants are capable of capturing the
mobility of a network as well as predicting the performance. The velocity estimators are used to
measure the speed and orientation of a mobile relative to its neighbours, given the presence of a
departing node. Based on the velocity estimators, the new scheme for mobility characterization
is capable of characterizing the mobility of a node that are associated with topological stability,
i. e. the node's speeds, orientations relative to its neighbouring nodes and its past epoch time.
iiiBIOPATTERN EU Network of Excellence (EU Contract 508803
Recommended from our members
Spreadable Connected Autonomic Networks (SCAN)
A Spreadable Connected Autonomic Network (SCAN) is a mobile network that automatically maintains its own connectivity as nodes move. We envision SCANs to enable a diverse set of applications such as self-spreading mesh networks and robotic search and rescue systems. This paper describes our experiences developing a prototype robotic SCAN built from commercial, off-the-shelf hardware, to support such applications. A major contribution of our work is the development of a protocol, called SCAN1, which maintains network connectivity by enabling individual nodes to determine when they must constrain their mobility in order to avoid disconnecting the network. SCAN1 achieves its goal through an entirely distributed process in which individual nodes utilize only local (2-hop) knowledge of the network's topology to periodically make a simple decision: move, or freeze in place. Along with experimental results from our hardware testbed, we model SCAN1's performance, providing both supporting analysis and simulation for the efficacy of SCAN1 as a solution to enable SCANs. While our evaluation of SCAN1 in this paper is limited to systems whose capabilities match those of our testbed, SCAN1 can be utilized in conjunction with a wide-range of potential applications and environments, as either a primary or backup connectivity maintenance mechanism
- …