Baseband in a LAN or other network indicates that pulses are used directly on the network medium to generate a signal with the encoded binary data. Spectrum of the amplitude of a base band in function of the frequency

In normal language: one signal flow across one conductor.

There is therefore no modulation on a carrier wave as in broadband networks where multiple channels are transmitted simultaneously. By using a base band, the system is relatively fault-sensitive and increases with the frequency and length of the cables. To allow multiple users to simultaneously use a baseband network, they allow packet switching.

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