An abbreviation for Internet Security Systems, a company that has been licensed by Microsoft to include its intrusion detection technology with ISA Server.
Internet Sharing Software. An application that allows all PCs on a network access the Internet simultaneously through a single modem and Internet Service Provider (ISP) account.
Internet sign-up server. An HTTP server that automates the task of adding new customers to an ISP's customer database. The Internet sign-up server collects information from each customer, adds the information to the ISP's customer database, and then passes a configuration packet back to the customer's desktop computer. The configuration packet contains information that is used to configure the customer's Internet browser for subsequent connection to the ISP's services.