Daniel Camara

A novel routing algorithm for ad hoc networks

A mobile ad hoc network (MANET) is comprised of mobile hosts that can communicate with two other using wireless links. In this paper we present a novel routing algorithm called GPSAL (GPS/ant-like routing algorithm) which is based on GPS (Global Positioning System) and mobile software agents modeled on ants for routing in ad hoc networks. We compare our algorithm to the location-aided routing (LAR) algorithm for MANET which is also based on GPS. Simulation results show that our algorithm has less overhead than LAR.

Direct code execution: revisiting library OS architecture for reproducible network experiments

We describe the first capability, to our knowledge, to execute nearly unmodified applications and Linux kernel code in the context of a widely-used open source discrete event networking simulator (ns-3). We propose Direct Code Execution (DCE), a framework that dramatically increases the number of available protocol models and realism available for ns-3 simulations. DCE meets the goals recently proposed for fully reproducible networking research and runnable papers, with the added benefits of 1) the ability of completely deterministic reproducibility, 2) the scalability that simulation time dilation offers, 3) capabilities supporting automated code coverage analysis, and 4) improved debuggability via execution within a single address space. In this paper, we describe in detail DCE, report on packet processing benchmarks and showcase key features of the framework with different use cases. We reproduce a previously published Multipath TCP (MPTCP) experiment and highlight how code coverage testing can be automated by showing results achieving 55-86% coverage of the MPTCP implementation. Then we demonstrate how network stack debugging can be easily performed and reproduced across a distributed system. Our first benchmarks are promising and we believe this framework can benefit the network community by enabling realistic, reproducible experiments and runnable papers.

A GPS/ant-like routing algorithm for ad hoc networks

A mobile ad hoc network (MANET) is comprised of mobile hosts that can communicate with each other using wireless links. In this paper we present a novel routing algorithm called GPSAL (GPS/ant-like routing algorithm) which is based on the GPS (Global Positioning System) and mobile software agents modeled on ants for routing in ad hoc networks. We compare our algorithm to the location-aided routing (LAR) (Ko and Vaidya 1998) algorithm for MANET which is also based on GPS. Simulation results show that our algorithm has less overhead than LAR.

Propagation of Public Safety Warning Messages: A Delay Tolerant Network Approach

This work presents an auxiliary mechanism to aid in the distribution of warning messages for Emergency Alert Systems (EAS). The main objectives of the proposed mechanism are to speed up and broaden the warning messages distribution process to provide to the public faster access to crucial information. EAS are public safety message systems designed to enable authorities to address the population in case of an emergency. This kind of system has been in use for a long time, however traditionally they are composed of radio/TV broadcast messages or sirens spread through endangered regions. This system on the other hand addresses the next generation of EAS systems that will be based on wireless computer networks and satellite technologies. The method proposed here is a complementary way to spread warning messages that not only successfully broadens the EAS reachability but also significantly speeds up the messages distribution process.

Cavalry to the rescue: Drones fleet to help rescuers operations over disasters scenarios

This paper proposes a drone based solution to help on the search and rescue activities over disaster scenarios. The proposed architecture is composed of specialized drones to accomplish specific tasks and an internal modules organization to grant they will be able to accomplish their objectives. Among the tasks we believe drones could excel performing over disaster scenarios we can highlight: providing a temporary communication structure, creating up-to-date maps of the affected region and searching for hot spots where the rescue teams may have more chances of finding victims. For example, drones may be equipped with infrared cameras, deep penetration radars, or even detect the radio signal from portable devices. All these activities require specific competences, and thus more than one kind of drone and sensor equipment are required to accomplish all of them. This drone based fleet, to be efficient and useful in the terrain needs to be autonomous and capable of self-organization.

Methodology for Formal Verification of Routing Protocols for Ad Hoc Wireless Networks

This paper describes a technique to apply formal methods to verify protocols for mobile ad hoc networks. In contrast to other related proposals, our solution does not attempt to model any particular network configuration. Instead, our solution focuses on the possible implications caused by network configurations to the behavior of a routing protocol for MANETs. Following this strategy we were able to find design errors in some well established protocols. The proposed technique uses formal verification, more specifically model checking, to detect, in a simple way, problems such as routing loops, delivery message failures and errors in the protocol state machine.

DCE: Test the real code of your protocols and applications over simulated networks

We present the Direct Code Execution (DCE) environment for ns-3, notable for being the first free open source framework for integrating Linux kernel and application code within a leading discrete-event network simulator. This new approach has many potential advantages over virtual-machine-based frameworks in terms of realism, reproducibility, avoidance of realtime execution constraints, configuration management, and the ability to debug a network-wide experiment from a single address space using common debugging tools. We provide an overview of DCE and illustrate some key features of this framework with two use cases, one involving thttpd, an HTTP server implementation, and another one involving the udp-perf traffic generator.

Multicast and Virtual Road Side Units for Multi Technology Alert Messages Dissemination

This paper presents a method to disseminate alert messages in the context of new emerging communication standards, such as LTE and Wave. The applications involving the broadcast of periodic messages, can be described using the MBMS (Multicast/Broadcast Multimedia Service). Public Safety alert systems perform one important task in the context of Public Safety Networks (PSNs). The method proposed here is responsible for delivering alert messages to the greatest number of people in a specified area. To accomplish this task a new method, Virtual Road Side Unit (vRSU) is proposed to help the authorities to reach isolated people. The system works even if the deployed structure is severed damaged, i.e. most part of the regular Road Side Units (RSU) are out of order. In our method nodes work cooperatively to propagate the message to other nodes, when re-propagating messages nodes, vRSUs, behave as regular RSUs. KeywordsPublic Safety; multicast; alert; LTE; data

Providing Billing Support in WiMAX Mesh Networks

A huge effort has been applied on the study of Wireless Mesh Networks (WMNs) over the last few years. As part of this effort the IEEE 802.16 Standard for Local and Metropolitan Area Networks specifies a mesh mode of operation. Although several technical aspects of the physical and medium access layers of the standard have been studied, only few works investigate how the WiMAX mesh mode architecture will handle billing aspects and paid access. Here we propose a billing architecture and present an accounting mechanism which allows WISPs to charge its users and also reward those who contribute forwarding packets. We evaluate the accounting mechanism through simulations and show its feasibility.

Topology management for group oriented networks

This paper proposes a topology management mechanism for hierarchical group oriented networks. The key innovative aspect of this paper is to consider different interest groups in the clustering formation process. For administrative or performance reasons sometimes it is required to organize nodes, located in the same geographical area, into different groups. This group-oriented topology management provides optimal routing for group members as well as for the last miles communication, where you only need to broadcast the message once to reach the entire interest group. Furthermore, it significantly improves the service provided to upper layers by creating a stable network topology. For example, when establishing a Public Safety Networks (PSN) to handle a disaster scenario the communication from the rescue teams may have no interest, or relation, with the communication hold by the law enforcement teams. In this case it makes sense to divide the network in two subgroups to improve routing and simplifying the medium access control. Here we propose a hierarchical network architecture to enable the organization of nodes into multiple interest groups in the same geographical area. Through simulations, we will show that how this architecture could be adapted to different PSN requirements and what are the key parameters.