Internet connection sharing, or just Internet sharing, is a term used to describe the technique of allowing more than one computer to simultaneously access the Internet with a single Internet connection. This may be via modem, cable modem, ADSL, ISDN, leased line or T1. In most cases, Internet sharing software uses Network Address Translation technology to achieve this.
When a computer is connected to the Internet it is assigned an IP address which allows it to communicate with other host computers elsewhere on the Internet. Public IP addresses are unique. There is only one computer in the world with a given address. This allows routers and other Internet hardware to direct packets of information toward the correct destination. Public IP addresses however are in limited supply. They are getting scarce and therefore expensive. When you use Internet sharing, you actually connect a whole LAN to the Internet using a single public IP address. All of the computers on the LAN except one can use private IP addresses.
Benefits of Internet connection sharing:
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