The Data Plane, also known as the forwarding plane, is the part of a network device (like a router or switch) that is responsible for the actual movement of data packets. Think of it as the "worker bee" of the network, carrying the data from one point to another.
Early network devices had a single plane that handled both routing and forwarding. As networks grew more complex and traffic volumes increased, this became a bottleneck. Separating the functions into distinct planes was a natural evolution to improve performance and scalability.
The separation of control and data planes is a key concept in SDN. It allows for centralized control of the network, making it more flexible, programmable, and easier to manage.
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A) Maintain routing tables and process routing protocols: This is the function of the Control Plane. It handles routing protocols (like OSPF, BGP) to build and maintain the routing tables.
C) Handle device management and configuration changes: This is the function of the Management Plane. It allows administrators to configure, monitor, and manage the device.
D) Process network authentication requests and maintain security policies: While security can be implemented in both the control and data planes, the core function of authentication and maintaining security policies is more closely tied to the Control Plane (for things like access control lists (ACLs) based on routing information) and often involves separate security appliances or servers.