Definition: The word "icsnet" means "Internet Cyber Security Network." It refers to a network that provides security for the Internet, protecting computer networks from cyber threats such as viruses, worms, and ransomware. The term was first used in 1973 by IBM. Detailed definition: - Internet Cyber Security Network: An internet service provider's (ISP) network designed to protect their customers' computers from cyber threats, which can include viruses, malware, and other cyber attacks. - "Internet" refers to the global network of computers connected together through a series of devices that run on different operating systems. The term is commonly used in computer networking to refer to the Internet as a whole. In 1973, IBM developed an Internet Security Network (ISCN) service model for its business unit, IBM Research. This was designed to protect the company's data centers and other critical infrastructure from cyber threats that could cause financial damage or disrupt normal operations. The term "icsnet" refers to a specific type of network that has been implemented by IBM and is now widely used in various industries as part of their overall cybersecurity strategy.