What does networking have to do with telephones?
Telephones and networking work hand in hand. The telecommunications industry has been gradually integrating with the computer industry and the computer industry has been gradually integrating with the telecommunications industry. The common goal is to join distantly located Local Area Networks into Metropolitan and Wide Area Networks (MANs and WANs).
1. Voice Channels

First thing that comes to mind is telephone systems and the phone at home. Talking to someone on the phone uses Voice Channels. This doesn't seem to have much to do with Networks!

We do use voice channels for modem communications to connect to BBSs (Bulletin Board Services) or to connect to the Internet. We also use voice channels to connect LANs using remote access. Due to the bandwidth limits on the Voice Channel, the data transfer rate is relatively slow.

Voice Channel: Dial-up connection through a modem using standard telephone lines. Typical Voice Channel communication rates are: 300, 1200, 2400, 9600, 14.4k, 19.2k, 28.8k, 33.6k and 56 kbps (bits per second).

2. Data Channels

Data channels are dedicated lines for communicating digitized voice and data. At the end of 1996, there was a major milestone where more data was communicated in North America's telecommunications system than voice.

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