1. Modem:
A Modem is a two in one device. That is it performs two functions. It is used to convert Digital signals to Analog, the process is Modulation (DAM) and the reverse process is converting Analog to Digital known as Demodulation (ADD).
2. Multiplexer(Many to One):
A multiplexer is a device that combines the inputs from different sources and produces one output. A demultiplexer does the reverse process.
3. Bridge:
It is a device used to link two same type of networks.
4. Router:
It is a device used to link two networks with different protocols.
5. Gateway:
It is a device used to link two networks of different types. It can convert a message from one code to another.
