On June 20, 2018, ns-3 project co-founder George Riley passed away from cancer. George was intimately involved in ns-3’s early development, both directly and through his students.
As a professor at Georgia Tech, George’s research focused on efficient and scalable simulations, and he and his PADS research group became involved with ns-2, developing a patch for ns-2 called PDNS (parallel/distributed ns). He also developed the Georgia Tech Network Simulator (GTNetS) around the same time; GTNetS was a packet-level simulator written in C++ with an emphasis on scalable, parallel simulations. The ns-3 simulator design drew from both of these predecessor tools, and several ns-3 features (the internet module architecture, nix-vector routing, the mpi module, BRITE routing support, the OnOffApplication and BulkSendApplication, the TCP RTT estimator) trace back to these original efforts. One can observe from George’s technical contributions [*] that simulation scalability and efficiency were common themes for his work.
George was also a strong advocate for education and ease-of-use with ns-3. He often reminded us to ‘keep it simple’, probably drawing on his experience in using GTNetS and ns-3 for many years while teaching at Georgia Tech. He regularly offered a graduate course in which students learned the fundamentals of discrete-event network simulation through the use of GTNetS and ns-3. George and his student John Abraham also created the Netanim network animator for visualizing ns-3 simulation output.
We will miss him, and we offer condolences to his friends and family.