SDN technology: a comparison between control plane and data plane
Control Plane
Let's say together that you're the cost of being in charge of the Ministry of Traffic for a city research that develops a good plan for traffic on the streets of that city buses and cars and everything that goes on in those cities and you have to draw up a traffic plan for cars coming from other cities to you or through you and that's what makes you in control of everything that goes on in your city and we can call you The Control Man and your mission is to study All streets and roads and choose the best routes for the passage of cars through you in addition to the need to communicate with the cities near you in order to tell them the traffic plan that you have made so that if a car is sent from a nearby city the official there will be aware of the best route that that car should take to reach its right destination and as soon as possible without falling into crowded places.
In the world of routers and sandwiches we have exactly the same idea which is the mind and intelligent controller Control Plane which studies and equips the best paths for the passage of all kinds of traffic or passing through you and this is either through static route or with the help of protocols such as RIP, OSPF, EIGRP communicates with other network devices at the Control Plane level also to choose the best routes and thus build traffic plans, which makes it the controller (theoretically) of the networks and in other words is the section that makes the routing process work on that device and summarize the following points:
Responsible for setting up tracks.
Responsible for building Routing Information Base.
Responsible for communicating with other networking devices and sharing communications information
Policy preparation polices.
There are a lot of points but I don't want to dive into them because we want to take advantage of the general concept to get to the SDN, so now imagine that all the control centers of a giant network like Google or Amazon, for example, are in one center or nucleus(SDN)how easy and flexible the control mechanism will become between all the devices of that network!.
Data Plane
Going back to our previous example, we will find that the Data Plane is these people responsible (traffic police) for the traffic of cars and buses or any means of transit that want to pass through the streets of that city directly and regardless of this level does not look at the shape of the vehicle that wants to pass unless instructions arrive from the classificationcontrol center, most importantly how to make it pass through my city or cross from one city to another and drop on the life of networks here The actual scrolling of the traffic is done, i.e. all that I get from data from one of the ports I put on the port to which you should go based on the instructions I receive through control planecontrol center, i.e. here the management process of managing the traffic and passing it to the correct tracks and in other words this section is the stupid section that only has to carry out the orders of its control centers and these are the most important points that he performs:
Responsible for managing traffic
Responsible for the transfer itself Transformation
Responsible for classifying and sorting the Classification
Responsible for the distribution of Data Parsing
So what did the SDN give us?
Before I answer this question, I will imagine a much bigger and more important question than all that has been mentioned so far, which is what the SDN is?
We say SDN as a term that does not refer to anything physical and specific is a modern approach that has led to the formation of a new architecture in the world of networks by making networks an open and free world that can be programmed and controlled smoothly and easily through large control centers called SDN Controller, which will play the role of Control Plane but at a greater level i.e. at a level that allows To combine different devices and companies in one place by making them devices that implement only i.e. Control Plane Devices by controlling them and sending commands and building applications that fit my network without committing to any software rule that manufacturers force me to as well as allow me to deal with the entire network as if it were one device and that is the answer to the first question what the SDN gave us.
Here we have reached the end of the second article to return hopefully to complete this series, which may be long, the more you read in it, I found many ideas that can be talked about in the future and in our next article we will talk about the mechanism of communication between control plane and data plane but at the level of SDN do not forget us from your invitations until then and you will be boded.
Thank you.
