Link analysis can be used to expose the underlying patterns and behaviors pertaining to national security and homeland defense related to such areas as terrorism and narcotics trafficking. The intelligence community can use link analysis to sift through vast amounts of data looking for connections, relationships, and critical links among their suspected targets. In the private sector, link analysis can be used to monitor online and offline transactions by fraud specialists. Link analysis is but the first data mining technique used to assist investigators and analysts in investigating such areas as money laundering, narcotic trafficking, and terrorism. Link analysis is already used to detect fraud by specialists in the insurance and telecom industries, as well as in the area of e-commerce.
Intelligence analysts and criminal investigators must often correlate enormous amounts of data about entities in fraudulent, political, terrorist, narcotics, and other criminal organizations and is a critical first step in the visualization of the data. This is accomplished by organizing it in a cohesive manner, in terms of relationships between people and organizations under investigation. One of the challenging aspects, unique to the intelligence community, is discovering patterns derived from nontraditional data sources ranging from free-text documents and message intercepts to video clips and audio streams. The data mining systems typically used by the intelligence community are comprehensive and extremely specialized, customized for their unique needs. In these situations, link analysis is but one component and technique used by these intelligence analysts.