Showing papers by "Jarrod Trevathan published in 2011"

Targeting the Strategies of a Bid Sniper

Abstract: Bid sniping is a dubious practice used in online auctions whereby a bidder makes a bid in the closing moments in an attempt to deny other bidders time to react. The primary goal for a bid sniper is to win the auction for the lowest price possible, without the risk of being forced into submitting any higher bids if there is competition for the item. This paper investigates the phenomenon of bid sniping and its prevalence in commercial online auctions. We seek to show the extent of bid sniping, understand the rationale of why it occurs, what effect this has on the other auction participants, and what can be done to prevent the practice. Based on this understanding, we present a software bidding agent that follows a bid sniping strategy. The agent has the ability to suppress an auction's price through knowing when to bid, how much to bid, how to deal with rivals, and when to cease bidding. We also propose a new online auction format that can eliminate/reduce the effect of bid sniping. The proposal adds an undisclosed random time-out extension to an auction's finishing time to entice bidders to bid their maximum amount immediately or risk being excluded from the auction.

The evolution of the SEMAT sensor network management system

Abstract: Smart Environmental Measurements and Analysis Technologies (SEMAT) is a multidisplinary project aimed at constructing smart sensor networks that can be deployed in aquatic settings. The SEMAT system has been developed based on the Sensor Abstraction Layer (SAL). SAL is a middleware integration platform which provides an interface for managing sensors, and viewing the sensed data regardless of the technologies involved. SAL has a graphical user interface application tool for user interaction, referred as the SAL-Client. The interface provides remote-access to the functionalities of SAL. However, the existing design for the SAL-Client has many limitations which detracts from its usefulness. This paper introduces the SEMAT sensor network management system and describes how it has evolved from the SAL-Client based on practical usage in a real world deployment. The current system design for SEMAT has been moving forward to provide support for the Open Geospatial Consortium Sensor Web Enablement standards (OGC-SWE) and also the current popular data streaming/buffering technologies. The SEMAT sensor network management system automates the process for data collection, calibration, quality assurance, data management, reports and maintenance.

Disarming the bid sniper

Abstract: Bid sniping is the most common strategy used in online auctions whereby the bidder places a bid in the closing seconds in order to win the auction. This denies other bidders the time to react and suppresses the final price. While bid sniping is beneficial to the winner, it disadvantages other bidders and the seller does not get the full amount of revenue s/he might otherwise have received in a truly competitive and fair auction. This paper proposes a method to help negate bid sniping as a dominant strategy for winning in online auctions. We propose an amendment to the auction format that allows for a random undisclosed time-out extension should new bids be received in the closing moments. This entices bidders to bid their true valuation up front, otherwise they risk having the auction terminate and therefore not accept any new bids. Several variations of the amended auction format are presented that effectively counteract bid snipers by making it difficult to gain any information by observing the underlying algorithm. To ensure the auction does not continue indefinitely, the format includes mechanisms that place random bounds on the size of, and number of extensions permitted. Our proposal also makes intelligent decisions to maximize the price for the seller based on the auction's bid volume. The size of the extension granted is based on the timing and aggressiveness of how bids are being submitted. To our knowledge, no existing online auctioneers offer such a comprehensive format for actively discouraging bid sniping.

Efficient batch authentication for hierarchical wireless sensor networks

Abstract: Authentication in wireless sensor networks is critical, as they are often deployed unattended in hostile environments and must transmit information over unsecured mediums. However, the cost of performing cryptographic operations is an extremely limiting factor because sensor devices and related equipment are constrained by storage and computational ability. The problem is further compounded by the fact that one device (typically a base station) may be required to perform a large number of verifications proportional to the number of sensing devices. This paper investigates the efficiency of message authentication in hierarchical wireless sensor network systems. Scenarios are explored for verifying messages as a batch process, thereby saving overhead and computation. If a device is incapable of performing verification, it can sign the batch and pass it up the hierarchy to another device to undertake the verification procedure. This effectively overcomes many problems with power, storage and computational constraints. We contrast two approaches based on message authentication codes and short digital signatures. A framework is presented for how digital signatures can be used for batch authentication within a hierarchical wireless sensor network.

Towards plug-and-play functionality in low-cost sensor network

Abstract: Plug-and-play functionality in sensor networks is becoming inevitable to make network configuration and reconfiguration flexible and cost effective. The IEEE 1451 standard brings forward the concept of Transducer Electronic Data Sheet (TEDS), which is a memory device attached to the transducer, storing detailed information to configure the corresponding transducer. In this paper we share our experiences of using TEDS to enable plug-and-play functionality within a low-cost sensor network.

Privacy and anonymity in untrusted data stores

Abstract: This paper describes a security problem involving an online data repository, which acts as a proxy for multiple companies allowing their customers to perform online services (e.g., pay invoices). The repository's host is trusted to honestly fulfil its duties in maintaining the data in a manner consistent with each companies' required services. However, the information stored by the repository remains private in that the repository's host cannot openly read any companies' operational data, nor does it learn the identities of any companies' customers. We contrast several approaches describing their viability for web deployment using existing technologies. This is a fundamentally new security problem with no established literature or clearly defined cryptographic solution. The project originated from a commercial attempt to design a secure online data archive. A sample implementation of the system is presented that allows a customer to pay and view invoices online via the data repository using a popular and widely available small business accountancy application.

A system for managing data provenance in in silico experiments

Abstract: In silico experiments use computers or computer simulation to speed up the rate at which scientific discoveries are made. However, the voluminous amounts of data generated in such experiments is often recorded in an ad hoc manner without regard to workflow, and often lacks rigorous business rules. The absence of stringent auditing and reporting policies makes it difficult to repeat experiments and largely denies independent parties the ability to verify study results. This paper presents a data provenance management system based on the utility of the ICAT metadata storage service as a viable schema for representing in silico experiments. The system provides a portal interface to integrate ICAT with job execution. We have built on a data repository which can handle arbitrary data size, complexity and type. This can be practically used to compare, validate and aid in the repetition of historic experiments. Furthermore, data can be verified via external repositories/sources which will ultimately enhance the scientific merit of in silico experimentation. Our proposed system augments existing applications and therefore does not require users to modify their current experimentation platform. A test case for a pharmacological study is presented to illustrate the proposed system's versatility for reporting and auditing of experiments and their results.

Benefits of building wireless sensor networks on commodity hardware and software stacks

Abstract: The majority of wireless sensor networks are built on bespoke platforms, that is, custom designed and built hardware with a light weight software stack. There are a number of advantages to this approach. First, the ability to closely match and minimise the resource requirements (e.g., power consumption and communications protocols) to those that are suitable for the intended deployment. Second, as an entire hardware and software stack is often designed or at least optimised for each deployment, the latest advances can be quickly incorporated. However, this model generally requires the expertise of hardware and software engineers to design and build the system. In turn, this increases the cost and tends to shift the focus away from the initial science towards the development of the wireless sensor networks. This paper explores the utility and practicality of building wireless sensor networks based on commercially available embedded single board computing platforms using standard consumer operating systems. Our test bed was built using Gumstix computing platform, running a Linux Operating System (OS) with a java-based middleware coupled to low-cost scientific grade sensors. Test deployments have found this to be a highly versatile solution, able to leverage the flexibility of commodity hardware and software while maintaining reasonable utility.

The Tropical Data Hub (TDH) – a virtual research environment for tropical science knowledge innovation and discovery

Abstract: The Tropical Data Hub (TDH) as an e-Research initiative to provide a data hosting infrastructure to congregate significant tropical environmental data sets. Tropical regions support some of the world's most diverse and unique ecosystems. However, these sensitive areas are coming under increased pressures from human activities, which significantly threaten their sustainability into the future. Therefore, a need exists for more informed use of environmental monitoring procedures to help better manage tropical regions. At present data is collected in disjoint repositories and is not visible/accessible for reuse by other lines of enquiry. Without this data being publicised, many opportunities are missed for holistic discovery of major trends that influence tropical ecosystems. The TDH serves as a focal point for amalgamating disparate data sources to facilitate data reuse, integration/searching and knowledge discovery by environmental researchers and government departments. This will provide researchers and planners access to extensive and readily available data that can be used to give a more accurate representation of the state of tropical regions and allow for more suitable environmental management practices to be devised. We present two visualisation tools that model data from the Tropical Data Hub. The first is for assessing land space across Northern Australia and the second is a system to rapidly assess the potential impacts of climate change on global biodiversity.