John R. Vacca is an information technology consultant and writer. The author of twenty-one books and more than 330 articles, his most recent titles includeInternet Security, VRML; Bringing Virtual Reality to the Internet, Official Netscape LiveWire Pro Book,andIntranet Security. John was also the configuration management specialist, computer specialist, and the computer security official for NASAs space station program (Freedom) and the Alpha until his early retirement from NASA in 1995.