Cross-layer Peer-to-Peer Computing in Mobile Ad Hoc Networks

The future information society is expected to rely heavily on wireless technology. Mobile access to the Internet is steadily gaining ground, and could easily end up exceeding the number of connections from the fixed infrastructure. Picking just one example, ad hoc networking is a new paradigm of wireless communication for mobile devices. Initially, ad hoc networking targeted at military applications as well as stretching the access to the Internet beyond one wireless hop. As a matter of fact, it is now expected to be employed in a variety of civilian applications. For this reason, the issue of how to make these systems working efficiently keeps the ad hoc research community active on topics ranging from wireless technologies to networking and application systems. In contrast to traditional wire-line and wireless networks, ad hoc networks are expected to operate in an environment in which some or all the nodes are mobile, and might suddenly disappear from, or show up in, the network. The lack of any centralized point, leads to the necessity of distributing application services and responsibilities to all available nodes in the network, making the task of developing and deploying application a hard task, and highlighting the necessity of suitable middleware platforms. This thesis studies the properties and performance of peer-to-peer overlay management algorithms, employing them as communication layers in data sharing oriented middleware platforms. The work primarily develops from the observation that efficient overlays have to be aware of the physical network topology, in order to reduce (or avoid) negative impacts of application layer traffic on the network functioning. We argue that cross-layer cooperation between overlay management algorithms and the underlying layer-3 status and protocols, represents a viable alternative to engineer effective decentralized communication layers, or eventually re-engineer existing ones to foster the interconnection of ad hoc networks with Internet infrastructures. The presented approach is twofold. Firstly, we present an innovative network stack component that supports, at an OS level, the realization of cross-layer protocol interactions. Secondly, we exploit cross-layering to optimize overlay management algorithms in unstructured, structured, and publish/subscribe platforms

The design of a generalised approach to the programming of systems of systems

The world's computing infrastructure is increasingly differentiating into self-contained sub-systems (e.g. Internet of Things installations, clouds, VANETs, ...), which are post-hoc composed to generate value-added functionality (“systems of systems”). Today, however, such system-of-systems composition is typically carried out in an ad-hoc and infrastructure-dependent manner, with obvious associated disadvantages. In this paper, we propose a generalised system-of-systems-oriented programming approach that enables programmers to manage the composition of systems without a need for intimate knowledge of their internals, and also facilitates dynamic and spontaneous system composition, as systems discover each other opportunistically in their environment

A novel DHT Routing Protocol for MANETs

The central challenge in Mobile Ad hoc Networks (MANETs) is to provide a stable routing strategy without depending on any central administration. This work presents and examines the working of Radio Ring Routing Protocol (RRRP), a DHT based routing protocol for MANETs inspired from structured overlays in the internet. This design joins effort in answering the fundamental question of efficiency of a DHT substrate compared to conventional routing in ad hoc networks

Fault localization in service-based systems hosted in mobile ad hoc networks

Fault localization in general refers to a technique for identifying the likely root causes of failures observed in systems formed from components. Fault localization in systems deployed on mobile ad hoc networks (MANETs) is a particularly challenging task because those systems are subject to a wider variety and higher incidence of faults than those deployed in fixed networks, the resources available to track fault symptoms are severely limited, and many of the sources of faults in MANETs are by their nature transient. We present a suite of three methods, each responsible for part of the overall task of localizing the faults occurring in service-based systems hosted on MANETs. First, we describe a dependence discovery method, designed specifically for this environment, yielding dynamic snapshots of dependence relationships discovered through decentralized observations of service interactions. Next, we present a method for localizing the faults occurring in service-based systems hosted on MANETs. We employ both Bayesian and timing-based reasoning techniques to analyze the dependence data produced by the dependence discovery method in the context of a specific fault propagation model, deriving a ranked list of candidate fault locations. In the third method, we present an epidemic protocol designed for transferring the dependence and symptom data between nodes of MANET networks with low connectivity. The protocol creates network wide synchronization overlay and transfers the data over intermediate nodes in periodic synchronization cycles. We introduce a new tool for simulation of service-based systems hosted on MANETs and use the tool for evaluation of several operational aspects of the methods. Next, we present implementation of the methods in Java EE and use emulation environment to evaluate the methods. We present the results of an extensive set of experiments exploring a wide range of operational conditions to evaluate the accuracy and performance of our methods.Open Acces

An adaptive approach to service discovery in ad hoc networks

Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

An adaptive approach to service discovery in ad hoc networks

Service discovery allows the interaction between network nodes to cooperate in activities or to share resources in client-server, multi-layer, as well as in peer-to-peer architectures. Ad hoc networks pose a great challenge in the design of efficient mechanisms for service discovery. The lack of infrastructure along with node mobility makes it difficult to build robust, scalable and secure mechanisms for ad hoc networks. This paper proposes a scalable service discovery architecture based on directory nodes organized in an overlay network. In the proposed architecture, directory nodes are dynamically created with the aim of uniformly covering the entire network while decreasing the query latency for a service (QoS) and the number of control messages for the sake of increased scalability.8th IFIP/IEEE International conference on Mobile and Wireless CommunicationRed de Universidades con Carreras en Informática (RedUNCI

Exploiting the power of multiplicity: a holistic survey of network-layer multipath

The Internet is inherently a multipath network: For an underlying network with only a single path, connecting various nodes would have been debilitatingly fragile. Unfortunately, traditional Internet technologies have been designed around the restrictive assumption of a single working path between a source and a destination. The lack of native multipath support constrains network performance even as the underlying network is richly connected and has redundant multiple paths. Computer networks can exploit the power of multiplicity, through which a diverse collection of paths is resource pooled as a single resource, to unlock the inherent redundancy of the Internet. This opens up a new vista of opportunities, promising increased throughput (through concurrent usage of multiple paths) and increased reliability and fault tolerance (through the use of multiple paths in backup/redundant arrangements). There are many emerging trends in networking that signify that the Internet's future will be multipath, including the use of multipath technology in data center computing; the ready availability of multiple heterogeneous radio interfaces in wireless (such as Wi-Fi and cellular) in wireless devices; ubiquity of mobile devices that are multihomed with heterogeneous access networks; and the development and standardization of multipath transport protocols such as multipath TCP. The aim of this paper is to provide a comprehensive survey of the literature on network-layer multipath solutions. We will present a detailed investigation of two important design issues, namely, the control plane problem of how to compute and select the routes and the data plane problem of how to split the flow on the computed paths. The main contribution of this paper is a systematic articulation of the main design issues in network-layer multipath routing along with a broad-ranging survey of the vast literature on network-layer multipathing. We also highlight open issues and identify directions for future work

04411 Abtracts Collection -- Service Management and Self-Organization in IP-based Networks

From 03.10.04 to 06.10.04, the Dagstuhl Seminar 04411 ``Service Management and Self-Organization in IP-based Networks\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available