As the Internet grew in the late 80's, it became ever clearer that organizations connecting to it needed a way to close the door to it as well, and only let in the wanted visitors. Thus the notion of the firewall took shape, and several visionaries played a role developing today's varieties, either foundation concepts or products, including William Cheswick, Steve Bellovin, Marcus Ranum, Nir Zuk, David Presotto and Fred Avolio. Ironically, today there is growing sentiment against the firewall, with some labeling it an impediment to e-commerce.
Firewall pioneer wants a super-secure blogging service, so he built his own
Perimeter security vs. inside security
From firewall to 'firebox' for the data center