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1. Ingress Process:
Each port is capable of passing tagged or untagged frames. Ingress Process identifies if the incoming frames contain a tag, and classifies the incoming frames belonging to a VLAN. Each port has its own Ingress rule. If an Ingress rule accepts tagged frames only, the switch will drop all incoming
When a tagged frame is received on a port, it carries a tag header that has an explicit VID. Ingress Process directly passes the tagged frame to Forwarding Process.
An untagged frame does not carry any VID to which it belongs. When an untagged frame is received, Ingress Process inserts a tag contained the PVID into the untagged frame. Each physical port has a default VID called PVID (Port VID). PVID is assigned to untagged frames or priority tagged frames (frames with null (0) VID) received on this port.
After Ingress Process, all frames have a
2. Forwarding Process:
The Forwarding Process makes forwarding decisions on the received frames
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