June 2025
Beginner to intermediate
1180 pages
37h 48m
English
Content preview from Linux
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29.3 Basic Firewall Principles
The term firewall is on everyone's lips, but there is no generally accepted definition for it. Firewall can refer to hardware, when it usually means a computer that is located between the local network and the internet. Most routers also contain basic firewall functions. However, firewall also often refers to a program that is installed on the computer and is intended to improve security if configured correctly. Some distributions include tools for configuring the firewall.
In this book, I use the term firewall to refer to the protection of TCP/IP traffic by a packet filter. Such a filter analyzes all network packets entering and leaving the computer. Depending on whether all rules are followed, the packets ...
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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.
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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.