by Sam Raincock
"Within the UK, details of past telephone connections are stored by the network providers. The minimum storage is advised by the Data Retention (EC Directive) Regulations. However, each network provider is able to disclose different types of information about past connection activity and this availability also changes over time. As a result, it is important to be familiar with what connection record information may be available to your case so you can make appropriate requests to obtain access to it…"
Read more at http://www.forensicfocus.com/sam-raincock