System administrators must be able to manage inbound and outbound network traffic as well as prevent unwelcome visitors. UNIX like systems offer several tools to successfully fulfill these tasks. TCP Wrappers is one of the oldest and this short article is trying to give you practical examples of its use.
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The Internet protocol suite is the set of communications protocols that implement the protocol stack on which the Internet and most commercial networks run. It has also been referred to as the TCP/IP protocol suite, which is named after two of the most important protocols in it: the Transmission Control Protocol (TCP) and the Internet Protocol (IP), which were also the first two networking protocols defined. Class Ranges, Special Ranges and Bit-Wise Representation of TCP/IP Network Classes are stated here for quick reference purposes.
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