What is the Data Plane?

Data Plane Definition

A part of every system engaging in data transfer, the data plane deals with incoming or user-generated traffic and decides what action to be taken. It co-exists with the control & management plane to form the telecommunication architecture that every communicative app follows. 

In routing, it’s responsible for data transfer for clients as long as a connection is active. With the help of protocols like HTTP, it manages remote conversations. The associated traffic passes via the routers. 

In plain words, you can consider a data plane as the table that a router refer to find out the data packet destination details. 

In general, the table will feature the data packet path details . But, it may feature a data packet discarding command. When a router encounters such a table, it provides ‘destination unreachable’ error code as the response. 

The implementation 

In apps following the old-schooled networking format, the deployment area for data planes is in firmware. Another plane, i.e. control and management plane, resides in software components. However, apps adopting the SDN networking model follow different implementations. 

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What Does The Data Plane Do?

To keep it simple, a data plane functions as a data traffic carrier. It will help traffic to reach their destination. For example, if a user requested to access the Facebook website, the data plane will take the traffic there. 

Data Plane will take the data packets of the traffic and pass them through the routers. The routing decisions are done by the control panel and happen only when data planes forward the traffic to the router. 

In general, its tasks include:

• Deploying routing logic of the control plane 
• Sending/Forwarding Data packets to the network 
• Assessing traffic destination with the help of forwarding and routing tables 

The information gathered from the above functions is used to take actions like: 

• Completing the communication processing, depending upon the data in control plane 
• Directing data packets while they commute 

The Process

The Data Plane takes the help of routing logic, present in the control plane. Also, the information mentioned in the forwarding and routing tables is extracted. Based on all this information, the data plane decides where and how to send the data packets. For example, it may forward them to network interfaces to complete the communication cycle.

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Control Vs. Data Plane 

Are they linked? Yes. 

The data plane behaves as per the routing decisions taken by control plane. They both, together, are crucial for integrating communication abilities into an app. 

But, are they the same? No. 

They have substantial differences to share. Let’s get familiar with key control plane vs data plane pointers. 

• Their Scope

We already know what the data plane is. Let’s learn a bit about a control plan that refers to all the processes deciding the path that data packets have to take. It’s linked with that router architecture part which is responsible for constructing network topology skeleton. 

The task of this is to actively participate in routing protocols and designing routing tables, routing rules, forwarding principles, network topology, and other aspects that are required for effective data plane functionality.

Its logic is capable of finding the ill-performing or redundant data packets and deciding the retirement time for them. With different router implementation scenarios, control planes will have access to different forwarding information bases. Regardless of the information base used by the control plane, the data plane always has to refer to it to plan its actions. 

• Their Computing Capability

The control plane takes care of the data plane’s configuration and shutting down. It is a software part. Consider control planes as the cooking instructions that help a cook to find out what all spices are required, for how long a dish should be cooked, and so on. But, it’s standardized.

Or, the control plane is the mind and the data plane is the body. Just as the mind decides what a human has to do in a given situation and gives instructions to the body, the control plane decides what action a router should take against a traffic or user request and the data plane implements those actions. 

• Their Main Function

The control plane is the decision-maker and the data plane as its implementation resource. The Control plane is handling routing while the data plane is responsible for switching. 

The router carries out different actions for these two planes. For instance, the router generates packets for the control plane. But, no packets are generated for the data plane. The router only permits data plane packets to pass through it.

• Their Role in Packet Switching

Data planes utilizes the details collected by the control plane to carry and forward data packets as per the instructions. 

For a long time, developers and IT professionals have been trying to have a solid conceptual separation of these two. Unix is a perfect example to understand this. Here, basic operations open and close to cater control planes. For data planes, operations read and write the data. 

• Their network optimization goals 

Data planes optimize to ensure high processing speed and operational simplicity. 

On the contrary, the control plane aims to permit configuration and seamlessly handle complex situations. Also, it simplifies things so much that data plane processing is quick while effectively policies handling happens.

• Their Dependencies

The Control plane is fully independent. It takes actions without anyone’s influence. The Data plane is not like that. It’s mainly dependable on the control plane. It won’t decide on its own how to transport the data packet. It will use the control plane’s finding and behave accordingly. 

• Their Tech Stacks

They both use different technology stacks while processing. For instance, the control plane relies on STP or Spanning Tree Protocol, RIP or Routing Information Protocol, and ARP or Address Resolution Protocol. Time to Live and IP header checksum is the part of the data plane. 

• For the k8s Context

When Kubernetes is concerned, the control plane is the collection of components that take standardized cluster decisions. The data plane here is the collection of worker nodes. The corresponding containers and pods of worker nodes are also included. 

• ‍For the Service Mesh context

Control plane’s part is to take care of policy enforcement and the establishment. The data plane here is made up of sidecar proxies that transport the control plane configurations. 

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The Data Plane In Kubernetes 

For cloud-native apps, Kubernetes is one of the many highly preferred approaches. More and more Kubernetes APIs are offered to the developers and their result-driven usage depends on effective management. 

When it comes to cloud-native app management, mention of the data plane, control plane, and management plane is imperative as all three ensure the future of an app. 

The Data plane in Kubernetes is a little different from the customary data plane. While it decides the data packet destination in general, it looks after every aspect that is required for seamless app performance in Kubernetes. 

For example, it features key performance metrics like latency, user experience, SLAs, policies, and customer behavior triggers. The more responsive a data plane would be, the better an app tends to behave.

The Data plane in Kubernetes differs from the traditional data plane when it comes to structuring. Where data packets are the part of the data plane in general, there are worker nodes in Kubernetes. Note that worker nodes don’t exist alone. Worker containers, pods, and kubelets are also present. 

Here, containers and pods transmit data using the kubelet agents. Kubelet agents are responsible for sharing conditions and states with databases and container engineers are responsible for state information maintenance. 

There are different specifications of per-mode pod handling. Each container engineer will have different limitations. The prime aim to design Kubernetes was to manage on-premise apps/ Hence, pod scaling was its basic offering. When its adoption in cloud-native started, auto pod scaling wasn't happening. 

To fix this issue, Kubernetes started scheduling the pods on compatible and cluster-registered nodes. This practice promised for pink health of a node so much so that it was capable of bearing a pod run. But, it caused certain Kubernetes cluster inefficiencies. 

The Data plane in Kubernetes consists of workloads, scaled pods, and infrastructure components and will experience most computing actions. Looking for waste reductions? Organizations, using Kubernetes, must look into the data plane. 

Kubelets are part of every mode and also accept configuration-related instructions from the control plane or API server. A customary Kubernetes cluster deploys etcd for the data plane. In modern clusters, etcd is replaced by MariaDB, MySQL, and SQLite.

It’s hard to predict how control and data planes will be located. In some clusters, they are collocated while a few clusters use different implement locations. 

If a cluster is involved extensively in fault tolerance, the existence of a minimum of two control plane nodes with a minimum of three data plane nodes is mandatory.

However, Kubernetes data plane nodes could be five or seven, based on the number of control plane nodes used.  

Conclusion

As we move more towards cloud-native applications, improved performance, quick transmission, and end-to-end management remain the top priorities. The Data plane, a telecommunication architecture-constructing element, is crucial for data packet transmission. We learned a lot about it in the post. Let’s have a quick overview. 

• With the data plane, data packets remain directionless.
• Its deployment is mainly in firmware 
• The Data plane requires control panel data to decide what to do when 
• Kubernetes data plane is a bit different than customary data plane as is all about worker nodes 

With all this, we hope you now have better clarity on the data plane, its importance, and how it differs from the control plane. For an organization that understands the data plane well, rest 2 planes will have no hassles in developing a modern app with great communication abilities.