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Statistics for Spatial Data.

"A Survey of Mobility Models for Ad Hoc Network Research," Wireless Comm. & Mobile Computing (WCMC) : Special issue on Mobile Ad Hoc Networking : Research

In the performance evaluation of a protocol for an ad hoc network, the protocol should be tested under realistic conditions including, but not limited to, a sensible transmission range, limited buffer space for the storage of messages, representative data traffic models, and realistic movements of the mobile users (i.e., a mobility model). This paper is a survey of mobility models that are used in the simulations of ad hoc networks. We describe several mobility models that represent mobile nodes whose movements are independent of each other (i.e., entity mobility models) and several mobility models that represent mobile nodes whose movements are dependent on each other (i.e., group mobility models). The goal of this paper is to present a number of mobility models in order to offer researchers more informed choices when they are deciding upon a mobility model to use in their performance evaluations. Lastly, we present simulation results that illustrate the importance of choosing a mobility model in the simulation of an ad hoc network protocol. Specifically, we illustrate how the performance results of an ad hoc network protocol drastically change as a result of changing the mobility model simulated.

/pdf/a-survey-of-mobility-models-for-ad-hoc-network-research-ygkxat400x.pdf

A survey of mobility models for ad hoc network research

http://www.csun.edu/~andrzej/COMP529-S05/papers/Mesh%20Networks%20Survey.pdf

Wireless mesh networks: a survey

Multi-layer ad hoc wireless networks with UAVs is an ideal infrastructure to establish a rapidly deployable wireless communication system any time any where in the world for military applications. In this tactical environment, information traffic is quite asymmetric. Ground fighting units are information consumers and receive far more data than they transmit. The up-link is used for sending requests for information and some networking configuration overhead with a few kilobits, while the down-link is used to return the data requested with megabits size (e.g. multimedia file of images and charts). Centralized intelligent channel assigned multiple access (C-ICAMA) is a MAC layer protocol proposed for ground backbone nodes to access UAV (unmanned aerial vehicle) to solve the highly asymmetric data traffic in this tactical environment. With it's intelligent scheduling algorithm, it can dynamically allocate bandwidth for up-link and downlink to fit the instantaneous status of asymmetric traffic. The results of C-ICAMA is very promising, due to the dynamic bandwidth allocation of asymmetric up-link and down-link, the access delay is tremendously reduced.

C-ICAMA, a centralized intelligent channel assigned multiple access for multi-layer ad-hoc wireless networks with UAVs

In this paper, we address the problem of destination anonymity for applications in mobile ad hoc networks where geographic information is ready for use in both ad hoc routing and Internet services. Geographic forwarding becomes a lightweight routing protocol in favor of the scenarios. Traditionally the anonymity of an entity of interest can be achieved by hiding it among a group of other entities with similar characteristics, i.e., an anonymity set. In mobile ad hoc networks, generating and maintaining an anonymity set for any ad hoc node is challenging because of the node mobility, consequently the dynamic network topology. We propose protocols that use the destination position to generate a geographic area called an anonymity zone (AZ). A packet for a destination is delivered to all the nodes in the AZ, which make up the anonymity set. The size of the anonymity set may decrease because nodes are mobile, yet the corresponding anonymity set management is simple. We design techniques to further improve node anonymity and reduce communication overhead. We use analysis and extensive simulation to study the node anonymity and routing performance, and to determine the parameters that most impact the anonymity level that can be achieved by our protocol.

/pdf/anonymous-geo-forwarding-in-manets-through-location-cloaking-34kmvutosk.pdf

Anonymous Geo-Forwarding in MANETs through Location Cloaking

Ciphertext-policy attribute-based encryption (CP-ABE) provides an encrypted access control mechanism for broadcasting messages. Basically, a sender encrypts a message with an access control policy tree which is logically composed of attributes; receivers are able to decrypt the message when their attributes satisfy the policy tree. A user's attributes stand for the properties that he currently owns. A user should keep his attributes up-to-date. However, this is not easy in CP-ABE because whenever one attribute changes, the entire private key, which is based on all the attributes, must be changed. In this paper, we introduce fading function, which renders attributes “dynamic” and allows users to update each attribute separately. We study how choosing fading rate for fading function affects the efficiency and security. We also compare our design with CP-ABE and find our scheme performs significantly better under certain circumstance.

Secure, selective group broadcast in vehicular networks using dynamic attribute based encryption

We present a new trust architecture-Situation-Aware Trust-to address several important trust issues in vehicular networks SAT includes three main components: an attribute-based policy control model for highly dynamic communication environments, a proactive trust model to build trust among vehicles, and prevent the breakage of existing trust, and an email-based social network trust system to enhance trust and to allow the set up of a decentralized trust framework To deploy SAT, we utilize identity-based cryptography to integrate entity trust, data trust, security policy enforcement, and social network trust, allocating a unique identity, and a set of attributes for each entity We conclude by presenting research challenges and potential research directions that extend this work

/pdf/situation-aware-trust-architecture-for-vehicular-networks-rofyrcsvy8.pdf

Situation-aware trust architecture for vehicular networks

In hostile environments, adversaries can launch passive attacks against interceptable routing information embedded in routing messages and data packets. Allowing adversaries to trace network routes and infer the motion pattern of nodes at the end of those routes may pose a serious threat to covert operations. In this paper we propose a feasible adversary model of such attacks, then present several instantiations and study the principles of designing corresponding countermeasures. We demonstrate that existing ad hoc routing protocols are vulnerable to passive attacks: in the feasible adversary model, (a) the location and motion patterns of mobile nodes can be traced, while (b) proactive and reactive/on-demand ad hoc routes across multiple mobile nodes can be visualized by the adversary. We conclude that ad hoc networks deployed in hostile environments need new countermeasures to resist such passive attacks.

Xiaoyan Hong

Papers

C-ICAMA, a centralized intelligent channel assigned multiple access for multi-layer ad-hoc wireless networks with UAVs

Anonymous Geo-Forwarding in MANETs through Location Cloaking

Secure, selective group broadcast in vehicular networks using dynamic attribute based encryption

Situation-aware trust architecture for vehicular networks

A new set of passive routing attacks in mobile ad hoc networks