Measurement Issues with Geo-positional Forensics

摘要

The objective of this paper is to discuss the measurement issues in geo-positional forensics and the need to consider these issues from a measurement perspective when geo-positional data is to be used in a digital forensics investigation. As such this is a positional paper looking at the challenges of using geo-positional data in digital investigations and identifying the opportunities to enhance digital investigations by including spatial data. The use of geo-positional data in digital investigations has the potential to contribute to measurement science where there are situations or cases where questions of criminal, unethical or nonprofessional behaviour arise in the for example measuring pollutants, contaminants, radioactivity and there is a need to measure the spatial location of these data as well as measure the amount or volume. In this paper the specific measurement issues associated with Global Positioning Systems (GPS) and geo-positional forensics will be discussed. The relationship between measurement science and digital forensics has been discussed previously [1]. Geo-positional forensics makes use of the advances in technology and the almost ubiquitous nature of devices which have global positional capacity to add a spatial dimension to digital evidence. The GPS technology has remained reasonably static over the last 10 years, but what has changed radically in the last 5 years there has been significant advance in the devices which utilise Global Positioning System (GPS) technologies, including smart phones, satellite navigation systems for cars and GPS tracking devices themselves. The new range of devices that are either specific GPS devices or embed GPS functionality provide a new avenue for digital investigators to collect an additional form of digital evidence. The growth in the number of devices with GPS capability also means that more of the crimes that are committed (either cybercrime or indeed traditional crimes) have the potential of containing GPS information with can be used as digital evidence in geo-positional forensics. The paper will focus on the use of Global Position System technologies and will not discuss other tracking technologies such as Radio Frequency Identification (RFID), Geographic Information Systems (GIS) or Wireless Local Area Networks (WLAN).