$4\mathrm{.}2-1.$ What's inside a router? Match the names of the principal router components $($A$,$B$,$C$,$D below$)$ with their function and whether they are in the network$-$layer data plane or control plane.

Question $32$ options:

$($D$)$ is $...$

$($A$)$ are $...$

$($C$)$ are $...$

$($B$)$ is $...$

$1.$

input ports, operating primarily in the data plane.

$2.$

the switching fabric, operating primarily in the data plane.

$3.$

output ports, operating primarily in the data plane.

$4.$

the routing processor, operating primarily in the control plane.

$5.$

input ports, operating primarily in the control plane.

$6.$

output ports, operating primarily in the control plane.

$7.$

the switching fabric, operating primarily in the control plane.

$8.$

the routing processor, operating primarily in the data plane.