Hey everyone, thanks for coming back to another chapter of Wi Fi fundamentals with location and analytics. This course will help you to muster the air. In our basic Wi Fi process we saw the exchange of management frames sent to our access point and back to the station. As they both try to establish a connection. The language Wi Fi speaks its protocol can be better understood. Once you are familiar with the OSI layer.
It will help you in troubleshooting and will position Wi Fi in the context of every network that you're a part of. What will you learn? We will understand the OSI layer the theoretical layer that shows how data moves along we will see On the two main layers which are related directly to Wi Fi, the MAC layer and the physical layer. The OSI layer is a theoretical model that helps us to understand how data moves along from one side to the other. It starts in the application side where it all begins, your browser, your email client, down to the physical layer, the cables, or in our case, the air, which is our medium. OSI layer has several representations.
Some include seven layers, but most of us tend to look at things through a five layer model. Wi Fi happens at the bottom layers, the Mac and the physical. Let's look at the process. Data can move along in any direction. We will look at it from top to bottom. In our application layer, the first layer, we have protocols as HTTP.
We use it in our browsers to get resources as URLs. For it to get from our browser to the resource, it uses the TCP stack that every operating system has. It allows it to transfer the data using internal ports and sessions. That is the second layer. TCP relies on the IP layer which gets us IP addresses and is responsible that the data will move along between routers. The IP layer relies on the data link layer, which is actually the MAC layer to shift the data on to the physical layer.
Which in turn is responsible to send it into the air or into an ethernet cable. As data moves on, it dresses up in different forms. As it gets the IP address, it is called a packet. As it moves to the MAC layer and the physical, it is called an MST, u, n PDU and PSD u respectively. complicated, don't worry, it is just a way to describe data in a different form in different layers. All Wi Fi protocols have the same Meckler almost the same we have seen some changes in the latest standards, but the difference lies mostly at the physical layer.
So let's go ahead and see what does the MAC layer actually do? Well, the MAC layer provides a variety of functions that supports the operation of your WiFi network. As its name implies, it is responsible to coordinate access to the shared physical air interface. So both the station and the access point can communicate effectively. You can think of it as the brains of your Wi Fi network. We actually see the Mac operations just about everywhere.
When our access point sends a destination broadcast frame, as in a beacon frame, it is processed at the stations receiving it in the MAC layer. The same goes for the probe request and in times when frames received when an error which is something that happens all the time due to interferences or bad signal, the Mac's responsibility is to retransmit the frames again. It also adds a physical hardware address to each frame. That is the MAC address. We have said that the MAC layer is our control tower. It controls the traffic in there and that is exactly what it is doing.
It is responsible for the discovery process, the management trainee needed to establish the connection and once everyone is connected, who gets to transmit and even managing the power saving of our station. The McClair is also responsible for the physical hardware address. Without it our planes could not be reach their destination. MAC address is used in location analytics as a unique identifier, though in recent years vendors are implementing MAC address randomizing algorithms. Next up the physical layer. See you soon