Breaking tradition a bit with a second IIS in the same week (BTW, when a foreign power changes its signature, it usually means something major is going on outside of normal patterns).
Link analysis is a tool used to help identify relationships between people, things or events. Modern approaches use computer-based tools that do complex data mining to find relationships that may not be immediately apparent.
In the late 1980s I was a counterintelligence analyst at HQs Air Force Office of Special Investigations, assigned primarily to the Asia-Pacific Desk. Back then, computers were still relatively new and analytical tools were lacking.
We used whiteboards and diagrams to do most of the link analysis and it is from that stubby-pencil era that today’s powerful computer tools have emerged.
Link analysis is used in the law enforcement business as well, especially in fraud and financial crimes investigations. Following money has become easier, and when you are able to find sources of funding – who’s writing the checks – you gain tremendous insight into who’s really pulling someone’s strings.