Telecom fraudsters are not always outside the confines of the organization.
Internal Employee Fraud is a significant contributor to fraud affecting enterprises. In the CFCA 2011 Telecom Fraud Survey they found that Internal/Employee Theft totaled $1.44 billion out of the over $40 billion dollars of Telecom Fraud each year.
Employees may use company phones to make premium number, personal, and long distance calls. In the worst-case scenario, employees may actively enable toll fraud.
Without detailed per call reporting it can be hard to identify who is making these calls or to implement policies to prevent these calls.