Data Plane (or) Forwarding Plane

DATA PLANE:

• As for the data plane, sometimes called the Forwarding Plane, this is basically anything that goes *through* the router, and not *to* the router.
• The data plane is the workhorse of the switching elements in our networks.
• It has the responsibility of parsing packet headers (or cells, SONET) in high speed search ASICs. It manages QOS, filtering, encapsulations, Queuing, Policing all of the reasons we had and still do in many cases purpose built silicon or custom ASIC designs.
• The data/forwarding plane must do those operations in the “Fast Path” to keep up with performance needs in data centers and core networks.  (https://en.wikipedia.org/wiki/Fast_path)
• A case here could be Arista’s 7124FX switch that have low latency as well FPGA for programming the data plane
• The functions of data plane are:

• Also known as Forwarding Plane
• Forwards traffic to the next hop along the path to the selected destination network according to control plane logic
• Data plane packets go through the router
• The routers/switches use what the control plane built to dispose of incoming and outgoing frames and packets

• Forwarding data planes typically come either centralized or distributed. This means the forwarding engine is either centrally located across the ethernet fabric/crossbar or pushed all the way to the edge. The more performance required the more that distributed forwarding is pushed to the edge.
• For example - when a LAN switch receives a frame in an interface in VLAN 3, the switch makes a forwarding decision based on the VLAN 3 entries in the MAC address table, and forwards the packet. All this logic focuses on forwarding the user's data, so it is part of a switch's data plane processing.