Mobile network operators are experiencing increased traffic as laptops become more portable and cell phones and other wireless devices add power, features and functions. The downside is that the growing population of mobile users taking advantage of voice, video and data services are drawing the attention of hackers, eavesdroppers, and other malefactors. By understanding the growing number of threats to their networks and what countermeasures to take to minimize security risks, mobile operators can protect their customers and their networks against many of the attacks that inevitably will take place. This white paper describes the most common attacks on mobile networks and what to do about them.