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Summary of First chapter

Summary
A connection to a computer network can be broken down into the physical connection, the logical connection, and the applications that interpret the data and display the information. Establishment and maintenance of the physical connection requires knowledge of PC components and peripherals. Connectivity to the Internet requires an adapter card, which may be a modem or a network interface card (NIC).


In the early 1960s modems were introduced to provide connectivity to a central computer. Today, access methods have progressed to services that provide constant, high-speed access.

The logical connection uses standards called protocols. The Transmission Control Protocol/Internet Protocol (TCP/IP) suite is the primary group of protocols used on the Internet. TCP/IP can be configured on a workstation using operating system tools. The ping utility can be used to test connectivity.

A web browser is software that is installed on the PC to gain access to the Internet and local web pages. Occasionally a browser may require plug-in applications. These applications work in conjunction with the browser to launch the program required to view special or proprietary files.

Computers recognize and process data using the binary, or Base 2, numbering system. Often the binary output of a computer is expressed in hexadecimal to make it easier to read. The ability to convert decimal numbers to binary numbers is valuable when converting dotted decimal IP addresses to machine-readable binary format. Conversion of hexadecimal numbers to binary, and binary numbers to hexadecimal, is a common task when dealing with the configuration register in Cisco routers.

Boolean logic is a binary logic that allows two numbers to be compared and a choice generated based on the two numbers. Two networking operations that use Boolean logic are subnetting and wildcard masking.

The 32-bit binary addresses used on the Internet are referred to as Internet Protocol (IP) addresses.

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