A Survey Report on Operating Systems for Tiny Networked Sensors

Wireless sensor network (WSN) has attracted researchers worldwide to explore the research opportunities, with application mainly in health monitoring, industry automation, battlefields, home automation and environmental monitoring. A WSN is highly resource constrained in terms of energy, computation and memory. WSNs deployment ranges from the normal working environment up to hostile and hazardous environment such as in volcano monitoring and underground mines. These characteristics of WSNs hold additional set of challenges in front of the operating system designer. The objective of this survey is to highlight the features and weakness of the opearting system available for WSNs, with the focus on the current application demands. The paper also discusses the operating system design issues in terms of architecture, programming model, scheduling and memory management and support for real time applications.Comment: 12 pages, Submitted to Journa

Behavior of Wireless Body-to-Body Networks Routing Strategies for Public Protection and Disaster Relief

Critical and public safety operations require real-time data transfer from the incident area(s) to the distant operations command center going through the evacuation and medical support areas. Any delay in communication may cause significant loss. In some cases, it is anticipated that the existing communication infrastructures can be damaged or out-of-service. It is thus required to deploy tactical ad-hoc networks to cover the operation zones. Routing data over the deployed network is a significant challenge with consideration to the operations conditions. In this paper we evaluate the performance of mutli-hop routing protocols while using different wireless technologies in an urban critical and emergency scenario. Using a realistic mobility model, Mobile Ad hoc, geographic based and data-centric routing protocols are evaluated with different communication technologies (i.e. WiFi IEEE 802.11; WSN IEEE 802.15.4; WBAN IEEE 802.15.6). It is concluded that, WiFi IEEE 802.11 is the best wireless technology with consideration to the packet reception rate and the energy consumption. Whereas, in terms of delay, WBAN IEEE 802.15.6 is the most efficient. With regards to the routing protocols, assuming that the location information is available, geographical based routing protocol with WiFi IEEE 802.11 performed much better compared to the others routing protocols. In case where the location information is unavailable, gradient based routing protocol with WBAN IEEE 802.15.6 seems the best combination.Comment: WiMob, Oct 2015, Abu Dhabi, United Arab Emirate

Achieving Congestion Diversity in Multi-hop Wireless Mesh Networks

This paper reports on the first systematic study of congestion-aware routing algorithms for wireless mesh networks to achieve an improved end-end delay performance. In particular, we compare 802.11 compatible implementations of a set of congestion-aware routing protocols against our implementation of state of the art shortest path routing protocol (SRCR). We implement congestion-aware routing algorithms Backpressure (BP), Enhanced-Backpressure (E-BP) adapted from [1], [2] suitably adjusted for 802.11 implementation. We then propose and implement Congestion Diversity Protocol (CDP) adapted from [3] recognizing the limitations of BP and E-BP for 802.11-based wireless networks. SRCR solely utilizes link qualities, while BP relies on queue differential to route packets. CDP and E-BP rely on distance metrics which take into account queue backlogs and link qualities in the network. E-BP computes its metric by summing the ETX and queue differential, while CDP determines its metric by calculating the least draining time to the destination. Our small testbed consisting of twelve 802.11g nodes enables us to empirically compare the performance of congestion-aware routing protocols (BP, E-BP and CDP) against benchmark SRCR. For medium to high load UDP traffic, we observe that CDP exhibits significant improvement with respect to both end-end delay and throughput over other protocols with no loss of performance for TCP traffic. Backpressure-based routing algorithms (BP and E-BP) show poorer performance for UDP and TCP traffic. Finally, we carefully study the effects of the modular approach to congestion-aware routing design in which the MAC layer is left intac

GNSS Time Synchronization in Vehicular Ad-Hoc Networks: Benefits and Feasibility

Time synchronization is critical for the operation of distributed systems in networked environments. It is also demanded in vehicular ad-hoc networks (VANETs), which, as a special type of wireless networks, are becoming increasingly important for emerging cooperative intelligent transport systems. Global navigation satellite system (GNSS) is a proven technology to provide precise timing information in many distributed systems. It is well recognized to be the primary means for vehicle positioning and velocity determination in VANETs. However, GNSS-based time synchronization is not well understood for its role in the coordination of various tasks in VANETs. To address this issue, this paper examines the requirements, potential benefits, and feasibility of GNSS time synchronization in VANETs. The availability of GNSS time synchronization is characterized by almost 100% in our experiments in high-rise urban streets, where the availability of GNSS positioning solutions is only 80%. Experiments are also conducted to test the accuracy of time synchronization with 1-PPS signals output from consumer grade GNSS receivers. They have shown 30-ns synchronization accuracy between two receivers of different models. All these experimental results demonstrate the feasibility of GNSS time synchronization for stringent VANET applications.Comment: 10 page

Underwater Optical Wireless Communications, Networking, and Localization: A Survey

Underwater wireless communications can be carried out through acoustic, radio frequency (RF), and optical waves. Compared to its bandwidth limited acoustic and RF counterparts, underwater optical wireless communications (UOWCs) can support higher data rates at low latency levels. However, severe aquatic channel conditions (e.g., absorption, scattering, turbulence, etc.) pose great challenges for UOWCs and significantly reduce the attainable communication ranges, which necessitates efficient networking and localization solutions. Therefore, we provide a comprehensive survey on the challenges, advances, and prospects of underwater optical wireless networks (UOWNs) from a layer by layer perspective which includes: 1) Potential network architectures; 2) Physical layer issues including propagation characteristics, channel modeling, and modulation techniques 3) Data link layer problems covering link configurations, link budgets, performance metrics, and multiple access schemes; 4) Network layer topics containing relaying techniques and potential routing algorithms; 5) Transport layer subjects such as connectivity, reliability, flow and congestion control; 6) Application layer goals and state-of-the-art UOWN applications, and 7) Localization and its impacts on UOWN layers. Finally, we outline the open research challenges and point out the future directions for underwater optical wireless communications, networking, and localization research.Comment: This manuscript is submitted to IEEE Communication Surveys and Tutorials for possible publicatio

A survey of communication protocols for internet of things and related challenges of fog and cloud computing integration

The fast increment in the number of IoT (Internet of Things) devices is accelerating the research on new solutions to make cloud services scalable. In this context, the novel concept of fog computing as well as the combined fog-to-cloud computing paradigm is becoming essential to decentralize the cloud, while bringing the services closer to the end-system. This article surveys e application layer communication protocols to fulfill the IoT communication requirements, and their potential for implementation in fog- and cloud-based IoT systems. To this end, the article first briefly presents potential protocol candidates, including request-reply and publish-subscribe protocols. After that, the article surveys these protocols based on their main characteristics, as well as the main performance issues, including latency, energy consumption, and network throughput. These findings are thereafter used to place the protocols in each segment of the system (IoT, fog, cloud), and thus opens up the discussion on their choice, interoperability, and wider system integration. The survey is expected to be useful to system architects and protocol designers when choosing the communication protocols in an integrated IoT-to-fog-to-cloud system architecture.Peer ReviewedPostprint (author's final draft

Understanding Security Requirements and Challenges in Internet of Things (IoTs): A Review

Internet of Things (IoT) is realized by the idea of free flow of information amongst various low power embedded devices that use Internet to communicate with one another. It is predicted that the IoT will be widely deployed and it will find applicability in various domains of life. Demands of IoT have lately attracted huge attention and organizations are excited about the business value of the data that will be generated by the IoT paradigm. On the other hand, IoT have various security and privacy concerns for the end users that limit its proliferation. In this paper we have identified, categorized and discussed various security challenges and state of the art efforts to resolve these challenges

A New Energy Efficient Approach Towards WASN Routing with Modified QCS Protocol

In today's world Wireless Ad-hoc sensor network, consists of small sensor nodes having limited resources, has a great potential to solve problems in various domain including disaster management. In this paper "QCS-protocol" is modified which was introduced in our previous paper [1] and named as "Modified QCS-protocol". This is the backbone of our Intelligent Energy Efficient Ad-hoc Sensor Network. Two other protocols "Irregular Information Transfer" & "Final Broadcast-Petrol Flow" protocol are also modified to enhance performance of the new version of QCS protocol to run the system properly and to make the network more energy efficient and perfect. The challenges in WASN are- limited node power, Ad-hoc organization of network and reliability. Most of the existing approaches addressed the problems separately, but not in a totality. This paper shows how the network can have unlimited life and all time readiness with overall stability to send information to the base station with minimum power dissipation with the help of multimode "same type" sensor nodes and type categorization of generated information. Moreover an effort is made to give some light to the implementation issues and analyzed overall performance of the network by MATLAB simulation.Comment: 18 pages, 14 figure

ROMANO: A Novel Overlay Lightweight Communication Protocol for Unified Control and Sensing of a Network of Robots

We present the Robotic Overlay coMmunicAtioN prOtocol (ROMANO), a lightweight, application layer overlay communication protocol for a unified sensing and control abstraction of a network of heterogeneous robots mainly consisting of low power, low-compute-capable robots. ROMANO is built to work in conjunction with the well-known MQ Telemetry Transport for Sensor Nodes (MQTT-SN) protocol, a lightweight publish-subscribe communication protocol for the Internet of Things and makes use its concept of "topics" to designate the addition and deletion of communication endpoints by changing the subscriptions of topics at each device. We also develop a portable implementation of ROMANO for low power IEEE 802.15.4 (Zigbee) radios and deployed it on a small testbed of commercially available, low-power, and low-compute-capable robots called Pololu 3pi robots. Based on a thorough analysis of the protocol on the real testbed, as a measure of throughput, we demonstrate that ROMANO can guarantee more than a $99.5\%$ message delivery ratio for a message generation rate up to 200 messages per second. The single hop delays in ROMANO are as low as 20ms with linear dependency on the number of robots connected. These delay numbers concur with typical delays in 802.15.4 networks and suggest that ROMANO does not introduce additional delays. Lastly, we implement four different multi-robot applications to demonstrate the scalability, adaptability, ease of integration, and reliability of ROMANO

Survey on Data-Centric based Routing Protocols for Wireless Sensor Networks

The great concern for energy that grew with the technological advances in the field of networks and especially in sensor network has triggered various approaches and protocols that relate to sensor networks. In this context, the routing protocols were of great interest. The aim of the present paper is to discuss routing protocols for sensor networks. This paper will focus mainly on the discussion of the data-centric approach (COUGAR, rumor, SPIN, flooding and Gossiping), while shedding light on the other approaches occasionally. The functions of the nodes will be discussed as well. The methodology selected for this paper is based on a close description and discussion of the protocol. As a conclusion, open research questions and limitations are proposed to the reader at the end of this paper