Sams Teach Yourself TCP/IP in 24 Hours, Fourth Edition

Dial-Up Networking

In the recent past, one of the most common methods for connecting to a TCP/IP network such as the Internet was through a phone line. Over the last few years, broadband techniques such as cable modems and DSL have reduced the importance of dial-up networking, but many computers still support dial-up connections, and the telephone modem is still an important connectivity tool in many areas.

A modem provides network access through a phone line. The term is short for MOdulate/DEModulate. Engineers created modems because the industry saw the enormous benefit of providing a way for computers to communicate over the world’s most accessible transmission medium: the global telephone system. Telephone lines have grown more sophisticated ...