Data Plane or Control Plane?

About this interactive

The data plane does the work; the control plane decides how the work is done. The lesson's Pony Express: carriers take each letter to the next station by its address, which is the data plane. When a station closes, someone tells every station to route around it, which is the control plane. Nothing written on a letter can change the route, and the route-maker never opens the letters. Routers are where the split began. The data plane forwards each packet out the interface its tables name, often in dedicated hardware such as a switch's ASICs. The control plane runs protocols such as OSPF to learn paths and build those tables, usually on the CPU. The same split shows up elsewhere: in a database, reading and writing records is data plane, changing the schema is control plane; in DNS, answering lookups is data plane, adding or removing records is control plane; in software-defined networking, the controller is the control plane; in zero trust, the policy engine decides and the enforcement point carries the traffic. Keeping the planes apart is segmentation inside one system: it limits what each part can affect, and it helps scale, performance and management, at the cost of some overhead and complexity. Some designs add a third, management plane.

What you'll learn

Classify a task as data plane (doing the day-to-day work: forwarding traffic, reading and writing records, answering lookups) or control plane (deciding how that work is done: building routes, changing a schema or a DNS zone, making access decisions)
Apply the split to routers, switches, databases, DNS, software-defined networking and zero trust, and explain the security benefit of keeping the two planes apart

Aligned to

CompTIA Security+

1.2 Summarize fundamental security concepts.

3.1 Compare and contrast security implications of different architecture models.

Key terms

Data Plane: The part of a network device responsible for actually forwarding packets toward their destinations based on rules and tables built by the control plane. In a router, the data plane looks up each packet's destination in the forwarding table and sends it out the correct interface at high speed.
Control Plane: The part of a network device responsible for making routing and policy decisions, such as running routing protocols to build and maintain the routing table, which the data plane then uses to forward traffic. The control plane handles the intelligence of the network while the data plane handles the actual packet forwarding.
Software-defined Network: A network architecture that decouples the control plane from the data plane, enabling centralized, programmable network management through software controllers rather than individual device configuration. SDN allows network behavior to be dynamically adjusted through software, simplifying management and enabling rapid provisioning.
Policy Engine: The component within the Zero Trust control plane that evaluates requests against defined rules and policies to determine whether access should be granted.
Policy Enforcement Point: The component in a Zero Trust architecture that intercepts a subject's request for a resource and enforces the access decision returned by the control plane.
Zero Trust: A security model that assumes no user or device is trusted by default and requires continuous verification.

Topics

Data Plane Control Plane Sdn Zero Trust Segmentation Interactive Streak Sort

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