w3pop.com :: ÍøÂçѧԺ :: Internet :: TCP/IP µØÖ·
TCP/IP uses 32 bits, or 4 numbers between 0 and 255 to address a computer.
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Each computer must have an IP address before it can connect to the Internet.
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Each IP packet must have an address before it can be sent to another computer.
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This is an IP address: 192.68.20.50.
This might be the same IP address: www.w3pop.com
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You will learn more about IP addresses and IP names in the next chapter of this tutorial.
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This is your IP address: "<%=request.ServerVariables("REMOTE_ADDR")%>"
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TCP/IP uses 4 numbers to address a computer. Each computer must have a unique 4 number address.
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The numbers are always between 0 and 255. Addresses are normally written as four numbers separated by a period like this: 192.168.1.50.
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TCP/IP uses 32 bits addressing. One computer byte is 8 bits. So TCP/IP uses 4 computer bytes.
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A computer byte can contain 256 different values:
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00000000, 00000001, 00000010, 00000011, 00000100, 00000101, 00000110, 00000111, 00001000 .......and all the way up to 11111111.
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Now you know why a TCP/IP address is 4 numbers between 0 and 255
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12 digit numbers are hard to remember. Using a name is easier.
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Names used for TCP/IP addresses are called domain names. w3schools.com is a domain name.
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When you address a web site like http://www.w3pop.com, the name is translated to a number by a DNS process (Domain Name Server).
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All over the world, a large number of DNS servers are connected to the Internet. DNS servers are responsible for translating domain names into TCP/IP addresses and update each other with new domain names.
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When a new domain name is registered together with a TCP/IP address, DNS servers all over the world are updated with this information.
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