In computer networking: A top-down approach featuring the Internet by J.F.Kurose & K.W.Ross described in the chapter of network layer. A router typically have input port, switching fabric and output port. Packet from the input port are routed in the switching fabric by looking up the routing table and forward to the appropiate output port. Then, packets are queued in the output port before the packets are transmitted. Normally, packet scheduling is implemented in the output port.
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