Supervisor engine and line card?

 Cisco switches like catalyst 6500 , nexus7k , nexus9k  have supervisor engine and line cards mounted on to the chassis. These switches have a chassis in which we install supervisor and line cards as a hardware.In the image at the bottom we have 2 supervisor engines and above them we have the line cards .Now supervisor engine is the cpu of the box that is responsible for building  the control plane and gives the dataplane information to the line cards so that forwarding can be done by the line cards.

for eg Routing information is gathered by the supervisor and is given to the line cards in the form of FIB and also a chassis can have multiple supervisors one act as primary and other as a standby supervisor

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