There are three main ways in which telephone evidence can have a significant impact on an investigation; 1) Cell Site Analysis, 2) Attribution Investigations, and 3) Mobile Phone Examinations. A brief overview of these areas of investigation is provided below.
In simple terms, 'Cell Site Analysis' is the examination of information recorded by the mobile networks (i.e. Three, EE/T-Mobile/Orange, Vodafone, O2) to investigate where a mobile phone might have been located and who may have been using it at a given time.
When a mobile phone is used to make or receive a call or text/short message (SMS), or when data connections (i.e. GPRS) are active, the mobile networks record information about these events. This data is known as the Call Data/Detail Records (CDRs). With experience, these records can be examined in great detail to establish patterns that may assist in identifying: a) who may have been using the mobile phone at any given time, b) whether there are deviations from 'normal' behaviour, and c) where the mobile phone may have been located.
With regard to the location of a mobile phone, this is determined using information about the cell sites/masts/towers used. Through the analysis of cell site usage patterns and by performing detailed radio measurements, investigations can be performed to determine the extent of the area in which a cell site, or collection of cell sites, could have been used.
Cell Site coverage can vary significantly from cell site to cell site as well as over time, therefore it is vital that call data records and radio survey data are interpreted accurately. Years of experience in performing Cell Site Analysis (involving 2G/GSM, 3G/UMTS and more recently 4G/LTE technologies), which includes making radio measurements in relatively inaccessible locations (inside, on foot, on public transport, covertly) enables detailed and thorough Cell Site Analysis investigations to be performed.
Please contact Digital Forensics Consultancy for further information.
Phone (UK Local Rate): 0330 13 30203
In addition to investigating where mobile phone may have been located at a particular time using Cell Site Analysis, the examination of cell site usage patterns over longer periods, and investigations regarding call/SMS, handset and connection patterns, enables a picture to be developed to establish who could (and who could not) have been using a particular mobile.
Experience in examining many millions of telephone records/events, and reducing vast numbers of records to meaningful easy to understand charts/maps, makes it possible to identify the factors of greatest significance to an investigation.
Should a mobile phone handset have been recovered, a detailed examination of its contents can reveal additional information about the user's activities. With experience in performing detailed mobile phone examinations and in interpreting and summarising the data (not just providing 'data dumps') it is possible to recover, identify and explain the important aspects of an examination to ensure key aspects are not overlooked.