Michael Healy

A comparative review of wireless sensor network mote technologies

In the past 10 years, wireless sensor networks have grown from a theoretical concept to a burgeoning modern technology. In this paper, we present a comparative review of several wireless sensor network motes. We analyze these WSN devices under a number of different parameters and criteria, including processing ability, expected lifetime and measurement capabilities. We compare and contrast the selected WSN motes under these different headings, highlighting the individual motes performance under each category

Wireless Sensor Node hardware: A review

Wireless sensor networks (WSN) are becoming increasingly popular, due to the benefits they bring to many applications as well as the increasing availability and maturity of the underlying technology. The fundamental building blocks of these networks are the sensor nodes themselves, the sensors attached to these nodes, and the software running on the nodes. A basic sensor node platform consists of a CPU, a radio and a power supply. For the last 10 years a number of research institutions and companies have been designing and producing nodes with these three components as a minimum. We review how these sensor nodes have evolved over this time and we also categorize the features of various platforms so as to enable an application developer to quickly determine which node is appropriate for their particular network or which features are desirable for inclusion on a custom built sensor platform.

Security for wireless sensor networks: A review

Due to the sensitive nature of the data gathered by many wireless sensor networks (WSNs) it is becoming critical that this data be protected. However, due to the constrained nature of the resources available on sensor nodes, traditional wireless networking security solutions are not viable due to their processing requirements, power consumption, speed and communications overhead. We review the threats and attacks faced by WSNs and then the current state of the art of dedicated WSN security protocols are examined and compared, focusing on their relative strengths and weaknesses.

Efficiently securing data on a wireless sensor network

Due to the sensitive nature of the data many wireless sensor networks are tasked to collect security of this data is an important concern. The best way to secure this data is to encrypt it using a secure encryption algorithm before it is transmitted over the air ways. However due to the constrained nature of the resources available on sensor nodes the cost, both in terms of power consumption and speed, of any software based encryption procedure can often out weigh the risks of the transmission being intercepted. We present a solution to reduce this cost of employing encryption by taking advantage of a resource already available on many sensor nodes; this resource being the encryption module available on the Chipcon CC2420 transceiver chip.

Historic land reclamation in the intertidal wetlands of the Shannon estuary, western Ireland

ABSTRACT There is abundant landscape evidence for extensive land reclamation conducted within the Shannon estuary wetlands. To date, little published research is available which identifies how much reclamation has occurred, its timing and the likely environmental implications. This paper addresses these questions on the basis of available cartographic and documentary data on land reclamation in this area. Identification of reclaimed land was based on the 2nd Edition Ordnance Survey of Ireland Map Series of 1924. These maps represent landscape features relating to reclamation, such as embankments, artificial arterial drainage channels and sluices. Using such indicators for the purpose of demarcation, the extent of the lands reclaimed has been mapped. Documentary information on reclamation schemes was acquired from the National Archives files on the Irish Quit Rent Office, including letters, memoranda, draft bills and Government Acts, legal documents and statements of account, and these support and supplement cartographic data. In total, approximately 6,500ha of the Shannon estuary lowlands were reclaimed for agriculture and other purposes. This has significantly altered the morphometric characteristics of the estuary, as embankments and revetments for flood protection have reduced the potential energy dissipation area and the water storage capacity of the estuarine wetlands. Reclamation has resulted in modification of the estuarine physical environment and its hydrodynamics, and altered the character of the wetland habitat in the estuary environs.

Analysis of Hardware Encryption Versus Software Encryption on Wireless Sensor Network Motes

Due to the sensitive and often personal nature of sensor data that many wireless sensor networks collect, the security of this data must be guaranteed. This is fast becoming an important concern for sensor networks which are finding applications in the military and home health domains. The best and often the only way to secure this data is to encrypt it using a secure encryption algorithm before it is transmitted over the air ways. Due to the constrained nature of the resources, memory and clock speeds, available on sensor nodes however, the cost, both in terms of power consumption and speed of encryption, of a software based encryption procedure can often outweigh the risks of the transmission being intercepted. This paper presents a solution to reduce this cost of employing encryption by taking advantage of a resource already available on many sensor nodes, including the Crossbow MICAz and MoteIV’s TmoteSKY; this resource being the AES encryption module available on the Chipcon CC2420 transceiver chip. The performance of using this method of securing data on a sensor network against using software implementations of some of the most popular cipher algorithms suitable for WSN is then analysed for both hardware platforms.

A Mote Interface for Fiber Optic Spectral Sensing With Real-Time Monitoring of the Marine Environment

The system presented in this paper demonstrates how a novel fiber optic based sensing platform, capable of detecting minute changes in the level of impurity in a liquid, can be incorporated onto a Mote-based platform enabling real time monitoring of a body of water. How these features can be used to detect representative samples, such as hydrocarbons and chlorophyll within a maritime environment, is demonstrated. Systems currently deployed worldwide include satellite mapping technology and high-cost water monitoring platforms. Growing international emphasis on the management of water quality is giving rise to an expansion of the international market for novel robust, miniaturized, intelligent water monitoring systems capable of measuring local environmentally detrimental events such as localised small scale chemical pollution.

Resources Implications for Data Security in Wireless Sensor Network Nodes

Due to the sensitive nature of the data gathered by many wireless sensor networks it is becoming critical that this data be protected. The obvious way to secure this data is to encrypt it using a secure encryption algorithm before it is transmitted over the (open) air ways. However due to the constrained nature of the resources available on sensor nodes the cost, in terms of power consumption, speed and communications overhead, of any software based encryption procedure can often out weigh the risks of the transmission being intercepted. In this paper we present a solution to reduce this cost of employing encryption by taking advantage of a resource already available on many sensor nodes; this resource being the AES hardware encryption module available on the Chipcon CC2420 transceiver chip.

Development of a prototyping platform for the integration of multiple fiber optic sensing devices to a SHIMMER ™ system for in-situ maritime monitoring.

the new SHIMMER prototyping platform has been augmented to allow for use as an environmental wireless sensing device. To date the Shimmer has been primarily used by the health industry. However, the prototype presented in this paper has been designed to allow for the integration of multiple sensing platforms, so that the Shimmer platform can be used for the monitoring of the maritime environment. The development of the software utilized for the sensing platform, Eyesweb and BioMobius, will also be demonstrated.

Power considerations when using high capacity data storage on wireless sensor motes

In recent years the onboard storage on wireless sensor motes has grown very dramatically, going from Kilobytes (KB) of available space to Gigabytes (GB). This massive increase has primarily come from the addition of support for micro or mini Secure Digital (SD) flash cards on the nodes. This extra storage capacity has led to new use cases for sensor motes which result in fewer data transmissions as a result of more in network aggregation and processing of the sensor data. The primary motivation for using this approach is that writing data to, and then reading data from the SD card, aggregating and processing this data before transmitting smaller packets, should be much more power efficient than transmitting the raw data using the onboard radio. We investigate the power profiles of applications that use SD cards for this purpose versus those that do not in order to determine if there is in fact any power savings, and if so, exactly how much energy can be saved.