February 2003
Intermediate to advanced
464 pages
12h 50m
English
book
Firewalls and Internet Security: Repelling the Wily Hacker, Second Edition
by William R. Cheswick, Steven M. Bellovin, Aviel D. Rubin
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Chapter 11. Firewall Engineering
Once upon a time, all firewalls were hand-constructed, perhaps from software obtained from various pioneers at DEC and TIS. For these early gateways, packet filtering was easy, but not very sophisticated, which meant that it was not very safe. There were no tools to keep track of TCP sessions at the packet level. (Two of us, Steve and Bill, designed a dynamic packet filter in September, 1992, based mostly on off-the-shelf components, but the implementation looked complex enough that it scared us off.)
Gateways back then were mostly at the application level. We built filters for FTP and SMTP access. Circuit gateways allowed modified clients to make connections to the Internet without IP connectivity—between intranet ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.