Tsutomu Shimomura
termsecurityhacking
The San Diego Supercomputer Center researcher whose own machines were broken into on Christmas Day 1994 using TCP sequence-number prediction and IP spoofing - and who then led the technical hunt that ended with Kevin Mitnick's arrest in February 1995.
The intrusion itself was a landmark: a textbook demonstration that a TCP connection could be hijacked by guessing the sequence numbers of a trusted host, which is why sequence-number randomisation exists today. The chase, written up with journalist John Markoff as Takedown, made both men famous and remains fiercely disputed - Mitnick's supporters read it as self-mythologising and see the press coverage itself as part of the punishment.
Also known as: shimomura, takedown, ip spoofing attack