Design of a reliable but low-cost wireless industrial network system using a bluetooth low energy Mesh network

Capstone Project submitted to the Department of Engineering, Ashesi University in partial fulfillment of the requirements for the award of Bachelor of Science degree in Electrical and Electronic Engineering, May 2020Many modern industrial plants have sensor actuator networks that allow operators on an industrial plant to receive data from sensors and send information to Actuators to operate plants efficiently. Most energy plants in Ghana such as Sony Asogli and Volta River Authorities Tema Thermal complex use guided media as a means of data communication. Guided media which is wired data communication has a couple of drawbacks. Problems with guided media include flexibility in re-arranging the sensor actuator topology in the plant. Another issue is the initial cost of wiring an entire plant. To make data communication between sensor actuators and operators on a plant more flexible in deployment the use of some suitable unguided media must be applied. Bluetooth Low Energy (BLE) mesh was the selected wireless media protocol due to its wide range, low power consumption constraints and interoperability due to a good number of devices having Bluetooth capability. My setup included multiple ESP 32 node MCU microcontrollers and a BLE compatible phone. Data from sensors could be received over long distance in real time using a flood mesh hopping algorithm. The experiment was a success and proved that BLE mesh can be used as a replacement for the traditional wired sensor networks.Ashesi Universit

The NASA SBIR product catalog

The purpose of this catalog is to assist small business firms in making the community aware of products emerging from their efforts in the Small Business Innovation Research (SBIR) program. It contains descriptions of some products that have advanced into Phase 3 and others that are identified as prospective products. Both lists of products in this catalog are based on information supplied by NASA SBIR contractors in responding to an invitation to be represented in this document. Generally, all products suggested by the small firms were included in order to meet the goals of information exchange for SBIR results. Of the 444 SBIR contractors NASA queried, 137 provided information on 219 products. The catalog presents the product information in the technology areas listed in the table of contents. Within each area, the products are listed in alphabetical order by product name and are given identifying numbers. Also included is an alphabetical listing of the companies that have products described. This listing cross-references the product list and provides information on the business activity of each firm. In addition, there are three indexes: one a list of firms by states, one that lists the products according to NASA Centers that managed the SBIR projects, and one that lists the products by the relevant Technical Topics utilized in NASA's annual program solicitation under which each SBIR project was selected

Ubiquitous Sensor Networking for Development (USN4D):An Application to Pollution Monitoring

This paper presents a new Ubiquitous Sensor Network (USN) Architecture to be used in developing countries and reveals its usefulness by highlighting some of its key features. In complement to a previous ITU proposal, our architecture referred to as “Ubiquitous Sensor Network for Development (USN4D)” integrates in its layers features such as opportunistic data dissemination, long distance deployment and localisation of information to meet the requirements of the developing world. Besides describing some of the most important requirements for the sensor equipment to be used in a USN4D setting, we present the main features and experiments conducted using the “WaspNet” as one of the wireless sensor deployment platforms that meets these requirements. Furthermore, building upon “WaspNet” platform, we present an application to Air pollution Monitoring in the city of Cape Town, in South Africa as one of the first steps towards building community wireless sensor networks (CSN) in the developing world using off-the-shelf sensor equipment

Discovery and Group Communication for Constrained Internet of Things Devices using the Constrained Application Protocol

The ubiquitous Internet is rapidly spreading to new domains. This expansion of the Internet is comparable in scale to the spread of the Internet in the ’90s. The resulting Internet is now commonly referred to as the Internet of Things (IoT) and is expected to connect about 50 billion devices by the year 2020. This means that in just five years from the time of writing this PhD the number of interconnected devices will exceed the number of humans by sevenfold. It is further expected that the majority of these IoT devices will be resource constrained embedded devices such as sensors and actuators. Sensors collect information about the physical world and inject this information into the virtual world. Next processing and reasoning can occur and decisions can be taken to enact upon the physical world by injecting feedback to actuators. The integration of embedded devices into the Internet introduces new challenges, since many of the existing Internet technologies and protocols were not designed for this class of constrained devices. These devices are typically optimized for low cost and power consumption and thus have very limited power, memory, and processing resources and have long sleep periods. The networks formed by these embedded devices are also constrained and have different characteristics than those typical in todays Internet. These constrained networks have high packet loss, low throughput, frequent topology changes and small useful payload sizes. They are referred to as LLN. Therefore, it is in most cases unfeasible to run standard Internet protocols on this class of constrained devices and/or LLNs. New or adapted protocols that take into consideration the capabilities of the constrained devices and the characteristics of LLNs, are required. In the past few years, there were many efforts to enable the extension of the Internet technologies to constrained devices. Initially, most of these efforts were focusing on the networking layer. However, the expansion of the Internet in the 90s was not due to introducing new or better networking protocols. It was a result of introducing the World Wide Web (WWW), which made it easy to integrate services and applications. One of the essential technologies underpinning the WWW was the Hypertext Transfer Protocol (HTTP). Today, HTTP has become a key protocol in the realization of scalable web services building around the Representational State Transfer (REST) paradigm. The REST architectural style enables the realization of scalable and well-performing services using uniform and simple interfaces. The availability of an embedded counterpart of HTTP and the REST architecture could boost the uptake of the IoT. Therefore, more recently, work started to allow the integration of constrained devices in the Internet at the service level. The Internet Engineering Task Force (IETF) Constrained RESTful Environments (CoRE) working group has realized the REST architecture in a suitable form for the most constrained nodes and networks. To that end the Constrained Application Protocol (CoAP) was introduced, a specialized RESTful web transfer protocol for use with constrained networks and nodes. CoAP realizes a subset of the REST mechanisms offered by HTTP, but is optimized for Machine-to-Machine (M2M) applications. This PhD research builds upon CoAP to enable a better integration of constrained devices in the IoT and examines proposed CoAP solutions theoretically and experimentally proposing alternatives when appropriate. The first part of this PhD proposes a mechanism that facilitates the deployment of sensor networks and enables the discovery, end-to-end connectivity and service usage of newly deployed sensor nodes. The proposed approach makes use of CoAP and combines it with Domain Name System (DNS) in order to enable the use of userfriendly Fully Qualified Domain Names (FQDNs) for addressing sensor nodes. It includes the automatic discovery of sensors and sensor gateways and the translation of HTTP to CoAP, thus making the sensor resources globally discoverable and accessible from any Internet-connected client using either IPv6 addresses or DNS names both via HTTP or CoAP. As such, the proposed approach provides a feasible and flexible solution to achieve hierarchical self-organization with a minimum of pre-configuration. By doing so we minimize costly human interventions and eliminate the need for introducing new protocols dedicated for the discovery and organization of resources. This reduces both cost and the implementation footprint on the constrained devices. The second, larger, part of this PhD focuses on using CoAP to realize communication with groups of resources. In many IoT application domains, sensors or actuators need to be addressed as groups rather than individually, since individual resources might not be sufficient or useful. A simple example is that all lights in a room should go on or off as a result of the user toggling the light switch. As not all IoT applications may need group communication, the CoRE working group did not include it in the base CoAP specification. This way the base protocol is kept as efficient and as simple as possible so it would run on even the most constrained devices. Group communication and other features that might not be needed by all devices are standardized in a set of optional separate extensions. We first examined the proposed CoAP extension for group communication, which utilizes Internet Protocol version 6 (IPv6) multicasts. We highlight its strengths and weaknesses and propose our own complementary solution that uses unicast to realize group communication. Our solution offers capabilities beyond simple group communication. For example, we provide a validation mechanism that performs several checks on the group members, to make sure that combining them together is possible. We also allow the client to request that results of the individual members are processed before they are sent to the client. For example, the client can request to obtain only the maximum value of all individual members. Another important optional extension to CoAP allows clients to continuously observe resources by registering their interest in receiving notifications from CoAP servers once there are changes to the values of the observed resources. By using this publish/subscribe mechanism the client does not need to continuously poll the resource to find out whether it has changed its value. This typically leads to more efficient communication patterns that preserve valuable device and LLN resources. Unfortunately CoAP observe does not work together with the CoAP group communication extension, since the observe extension assumes unicast communication while the group communication extension only support multicast communication. In this PhD we propose to extend our own group communication solution to offer group observation capabilities. By combining group observation with group processing features, it becomes possible to notify the client only about certain changes to the observed group (e.g., the maximum value of all group members has changed). Acknowledging that the use of multicast as well as unicast has strengths and weaknesses we propose to extend our unicast based solution with certain multicast features. By doing so we try to combine the strengths of both approaches to obtain a better overall group communication that is flexible and that can be tailored according to the use case needs. Together, the proposed mechanisms represent a powerful and comprehensive solution to the challenging problem of group communication with constrained devices. We have evaluated the solutions proposed in this PhD extensively and in a variety of forms. Where possible, we have derived theoretical models and have conducted numerous simulations to validate them. We have also experimentally evaluated those solutions and compared them with other proposed solutions using a small demo box and later on two large scale wireless sensor testbeds and under different test conditions. The first testbed is located in a large, shielded room, which allows testing under controlled environments. The second testbed is located inside an operational office building and thus allows testing under normal operation conditions. Those tests revealed performance issues and some other problems. We have provided some solutions and suggestions for tackling those problems. Apart from the main contributions, two other relevant outcomes of this PhD are described in the appendices. In the first appendix we review the most important IETF standardization efforts related to the IoT and show that with the introduction of CoAP a complete set of standard protocols has become available to cover the complete networking stack and thus making the step from the IoT into the Web of Things (WoT). Using only standard protocols makes it possible to integrate devices from various vendors into one bigWoT accessible to humans and machines alike. In the second appendix, we provide an alternative solution for grouping constrained devices by using virtualization techniques. Our approach focuses on the objects, both resource-constrained and non-constrained, that need to cooperate by integrating them into a secured virtual network, named an Internet of Things Virtual Network or IoT-VN. Inside this IoT-VN full end-to-end communication can take place through the use of protocols that take the limitations of the most resource-constrained devices into account. We describe how this concept maps to several generic use cases and, as such, can constitute a valid alternative approach for supporting selected applications

Discovery and group communication for constrained Internet of Things devices using the Constrained Application Protocol

The ubiquitous Internet is rapidly spreading to new domains. This expansion of the Internet is comparable in scale to the spread of the Internet in the ’90s. The resulting Internet is now commonly referred to as the Internet of Things (IoT) and is expected to connect about 50 billion devices by the year 2020. This means that in just five years from the time of writing this PhD the number of interconnected devices will exceed the number of humans by sevenfold. It is further expected that the majority of these IoT devices will be resource constrained embedded devices such as sensors and actuators. Sensors collect information about the physical world and inject this information into the virtual world. Next processing and reasoning can occur and decisions can be taken to enact upon the physical world by injecting feedback to actuators. The integration of embedded devices into the Internet introduces new challenges, since many of the existing Internet technologies and protocols were not designed for this class of constrained devices. These devices are typically optimized for low cost and power consumption and thus have very limited power, memory, and processing resources and have long sleep periods. The networks formed by these embedded devices are also constrained and have different characteristics than those typical in todays Internet. These constrained networks have high packet loss, low throughput, frequent topology changes and small useful payload sizes. They are referred to as LLN. Therefore, it is in most cases unfeasible to run standard Internet protocols on this class of constrained devices and/or LLNs. New or adapted protocols that take into consideration the capabilities of the constrained devices and the characteristics of LLNs, are required. In the past few years, there were many efforts to enable the extension of the Internet technologies to constrained devices. Initially, most of these efforts were focusing on the networking layer. However, the expansion of the Internet in the 90s was not due to introducing new or better networking protocols. It was a result of introducing the World Wide Web (WWW), which made it easy to integrate services and applications. One of the essential technologies underpinning the WWW was the Hypertext Transfer Protocol (HTTP). Today, HTTP has become a key protocol in the realization of scalable web services building around the Representational State Transfer (REST) paradigm. The REST architectural style enables the realization of scalable and well-performing services using uniform and simple interfaces. The availability of an embedded counterpart of HTTP and the REST architecture could boost the uptake of the IoT. Therefore, more recently, work started to allow the integration of constrained devices in the Internet at the service level. The Internet Engineering Task Force (IETF) Constrained RESTful Environments (CoRE) working group has realized the REST architecture in a suitable form for the most constrained nodes and networks. To that end the Constrained Application Protocol (CoAP) was introduced, a specialized RESTful web transfer protocol for use with constrained networks and nodes. CoAP realizes a subset of the REST mechanisms offered by HTTP, but is optimized for Machine-to-Machine (M2M) applications. This PhD research builds upon CoAP to enable a better integration of constrained devices in the IoT and examines proposed CoAP solutions theoretically and experimentally proposing alternatives when appropriate. The first part of this PhD proposes a mechanism that facilitates the deployment of sensor networks and enables the discovery, end-to-end connectivity and service usage of newly deployed sensor nodes. The proposed approach makes use of CoAP and combines it with Domain Name System (DNS) in order to enable the use of userfriendly Fully Qualified Domain Names (FQDNs) for addressing sensor nodes. It includes the automatic discovery of sensors and sensor gateways and the translation of HTTP to CoAP, thus making the sensor resources globally discoverable and accessible from any Internet-connected client using either IPv6 addresses or DNS names both via HTTP or CoAP. As such, the proposed approach provides a feasible and flexible solution to achieve hierarchical self-organization with a minimum of pre-configuration. By doing so we minimize costly human interventions and eliminate the need for introducing new protocols dedicated for the discovery and organization of resources. This reduces both cost and the implementation footprint on the constrained devices. The second, larger, part of this PhD focuses on using CoAP to realize communication with groups of resources. In many IoT application domains, sensors or actuators need to be addressed as groups rather than individually, since individual resources might not be sufficient or useful. A simple example is that all lights in a room should go on or off as a result of the user toggling the light switch. As not all IoT applications may need group communication, the CoRE working group did not include it in the base CoAP specification. This way the base protocol is kept as efficient and as simple as possible so it would run on even the most constrained devices. Group communication and other features that might not be needed by all devices are standardized in a set of optional separate extensions. We first examined the proposed CoAP extension for group communication, which utilizes Internet Protocol version 6 (IPv6) multicasts. We highlight its strengths and weaknesses and propose our own complementary solution that uses unicast to realize group communication. Our solution offers capabilities beyond simple group communication. For example, we provide a validation mechanism that performs several checks on the group members, to make sure that combining them together is possible. We also allow the client to request that results of the individual members are processed before they are sent to the client. For example, the client can request to obtain only the maximum value of all individual members. Another important optional extension to CoAP allows clients to continuously observe resources by registering their interest in receiving notifications from CoAP servers once there are changes to the values of the observed resources. By using this publish/subscribe mechanism the client does not need to continuously poll the resource to find out whether it has changed its value. This typically leads to more efficient communication patterns that preserve valuable device and LLN resources. Unfortunately CoAP observe does not work together with the CoAP group communication extension, since the observe extension assumes unicast communication while the group communication extension only support multicast communication. In this PhD we propose to extend our own group communication solution to offer group observation capabilities. By combining group observation with group processing features, it becomes possible to notify the client only about certain changes to the observed group (e.g., the maximum value of all group members has changed). Acknowledging that the use of multicast as well as unicast has strengths and weaknesses we propose to extend our unicast based solution with certain multicast features. By doing so we try to combine the strengths of both approaches to obtain a better overall group communication that is flexible and that can be tailored according to the use case needs. Together, the proposed mechanisms represent a powerful and comprehensive solution to the challenging problem of group communication with constrained devices. We have evaluated the solutions proposed in this PhD extensively and in a variety of forms. Where possible, we have derived theoretical models and have conducted numerous simulations to validate them. We have also experimentally evaluated those solutions and compared them with other proposed solutions using a small demo box and later on two large scale wireless sensor testbeds and under different test conditions. The first testbed is located in a large, shielded room, which allows testing under controlled environments. The second testbed is located inside an operational office building and thus allows testing under normal operation conditions. Those tests revealed performance issues and some other problems. We have provided some solutions and suggestions for tackling those problems. Apart from the main contributions, two other relevant outcomes of this PhD are described in the appendices. In the first appendix we review the most important IETF standardization efforts related to the IoT and show that with the introduction of CoAP a complete set of standard protocols has become available to cover the complete networking stack and thus making the step from the IoT into the Web of Things (WoT). Using only standard protocols makes it possible to integrate devices from various vendors into one bigWoT accessible to humans and machines alike. In the second appendix, we provide an alternative solution for grouping constrained devices by using virtualization techniques. Our approach focuses on the objects, both resource-constrained and non-constrained, that need to cooperate by integrating them into a secured virtual network, named an Internet of Things Virtual Network or IoT-VN. Inside this IoT-VN full end-to-end communication can take place through the use of protocols that take the limitations of the most resource-constrained devices into account. We describe how this concept maps to several generic use cases and, as such, can constitute a valid alternative approach for supporting selected applications

Automotive Ethernet architecture and security: challenges and technologies

Vehicle infrastructure must address the challenges posed by today's advances toward connected and autonomous vehicles. To allow for more flexible architectures, high-bandwidth connections and scalability are needed to connect many sensors and electronic control units (ECUs). At the same time, deterministic and low latency is a critical and significant design requirement to support urgent real-time applications in autonomous vehicles. As a recent solution, the time-sensitive network (TSN) was introduced as Ethernet-based amendments in IEEE 802.1 TSN standards to meet those needs. However, it had hurdle to be overcome before it can be used effectively. This paper discusses the latest studies concerning the automotive Ethernet requirements, including transmission delay studies to improve worst-case end-to-end delay and end-to-end jitter. Also, the paper focuses on the securing Ethernet-based in-vehicle networks (IVNs) by reviewing new encryption and authentication methods and approaches

A Decentralized Architecture for Active Sensor Networks

This thesis is concerned with the Distributed Information Gathering (DIG) problem in which a Sensor Network is tasked with building a common representation of environment. The problem is motivated by the advantages offered by distributed autonomous sensing systems and the challenges they present. The focus of this study is on Macro Sensor Networks, characterized by platform mobility, heterogeneous teams, and long mission duration. The system under consideration may consist of an arbitrary number of mobile autonomous robots, stationary sensor platforms, and human operators, all linked in a network. This work describes a comprehensive framework called Active Sensor Network (ASN) which addresses the tasks of information fusion, decistion making, system configuration, and user interaction. The main design objectives are scalability with the number of robotic platforms, maximum flexibility in implementation and deployment, and robustness to component and communication failure. The framework is described from three complementary points of view: architecture, algorithms, and implementation. The main contribution of this thesis is the development of the ASN architecture. Its design follows three guiding principles: decentralization, modularity, and locality of interactions. These principles are applied to all aspects of the architecture and the framework in general. To achieve flexibility, the design approach emphasizes interactions between components rather than the definition of the components themselves. The architecture specifies a small set of interfaces sufficient to implement a wide range of information gathering systems. In the area of algorithms, this thesis builds on the earlier work on Decentralized Data Fusion (DDF) and its extension to information-theoretic decistion making. It presents the Bayesian Decentralized Data Fusion (BDDF) algorithm formulated for environment features represented by a general probability density function. Several specific representations are also considered: Gaussian, discrete, and the Certainty Grid map. Well known algorithms for these representations are shown to implement various aspects of the Bayesian framework. As part of the ASN implementation, a practical indoor sensor network has been developed and tested. Two series of experiments were conducted, utilizing two types of environment representation: 1) point features with Gaussian position uncertainty and 2) Certainty Grid maps. The network was operational for several days at a time, with individual platforms coming on and off-line. On several occasions, the network consisted of 39 software components. The lessons learned during the system's development may be applicable to other heterogeneous distributed systems with data-intensive algorithms