Everyone, thanks for coming back to another chapter in Wi Fi fundamentals with location and analytics. This course will help you to muster the air. We are continuing with the OSI layer, the theoretical model that describes how a data moves from the application side to the physical layer. In Wi Fi. Everything happens in the bottom up two layers, the physical and the data link. The MAC layer, which is actually the data link layer, as we saw previously is the brains.
It controls and manages the data that arrives and passes it to the physical layer or from the physical layer towards the application side. The physical layer is responsible for the transmission and reception of frames. Let's see how it works. The physical layer is the bread and meat of our Wi Fi standards. Whenever you hear or read on your access point box that it supports 802 11 ac ad. It is the physical layer standard that your access point supports.
The different standards dictate the operating frequencies of your Wi Fi station, supported data rate, modulation, and more. In Ethernet, the responsibility of the physical layer is to carry the media over the physical hardware. The cables in Wi Fi we are dealing with frequencies, bands and channels. Air is our medium physical layer is responsible for many operations in your life. Find network. Part of them is to prepare the frames for transmission.
Use different modulation according to the near ness of your station and access point. Change the radio channels according to the environment condition if they're crowded, we can see that the different standards way back up until nowadays supports different data rates, number of available channels, channels with different techniques that spreads the signal in the year is OFDM, which we will look at them as we continue in this course. And collision avoidance techniques. Remember that Wi Fi is over the air, it must avoid interferences. In different conditions, we can see clearly that you can use high data rates at a short range. You can use low data rate at the longer range data rate is correlated directly to distance and signals condition.
The farther you are, the higher the rssi. And the smaller the signal to noise ratio and the smaller data rate. All right, we're progressing and next up is channel access. How your Wi Fi network managers each station and ape is turned to transmit frames in the air using csma. ca See you soon