in computer networking, queues are important concepts.
there are input queue and output queue in routers.
It is said, input queue can be divided into N queues, each of which correspond to 1 output port.
but there are also queues with different priorities.
I'm very confused. how queues are implemented in routers? why it is so flexible to divide queues? sometimes divide into N queues, sometimes, divide into queues with different priorities?
besides, there is a concept called
speedup, which means the line speed of output port is N times of that of input queues, so that when packets from N input ports are destined to an output port, there is no blocking. But since an output port is connected to an input port of another router, this means the input port line speed of the other router is N times of the previous router, which seems ridiculous. Am I wrong somewhere?