1. A network
switch is a computer networking device that connects network segments.
The term commonly refers to a Network bridge that processes and routes data at the Data link layer (layer 2) of the OSI model. Switches that additionally process data at the Network layer (layer 3 and above) are often referred to as Layer 3 switches or Multilayer switches.
The term network switch does not generally encompass unintelligent or passive
network devices such as hubs and repeaters.
2. Electro-mechanical device having distinct states, usually ON and Off, (or open and closed).
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