LOIC: LOIC (open source network attack application) LOIC: LOIC: LOIC is an open source network attack application, written in C#. LOIC LOIC: was initially developed by Praetox Technologies, but later it was LOIC: released into the public domain LOIC: LOIC: LOIC performs a denial-of-service (DoS) attack (or when used by multiple LOIC: individuals, a DDoS attack) on a target site by flooding the server with LOIC: TCP packets, UDP packets, or HTTP requests with the intention of LOIC: disrupting the service of a particular host. People have used LOIC to LOIC: join voluntary botnets.