I like to work in your back to Cy Berries MT. A 93 66
network and Fundamentals certification Prep course.
As a reminder, This is a continuation of modern number two.
In the previous modules, we discussed the following items. We discussed the Oise I model. We looked at the analysis and comparison. We looked at a riel vertical communication as well as effective hard on the communication.
Now what we're gonna do not discuss the seven layers off the ice tomorrow,
the two layers will be discussed. Doing this particular presentation is the physical layer as well, asked a data link layer. Let's begin by first are taking a look at a pre assessment course. Turn
which layer in us our model. Do the Mac address and switches use? Is it a physical?
Is it be gotta link, or is it C network? Or is it d transport?
If you select the beat, you're absolutely correct because that's the data link. Clear again what it does, establishes and maintains and decide how transfers compass over the physical layer.
Now, if you recall, we mentioned that the Seven Letters or Esam Maher is a reference mark. It represents specifications functions, activities that need to occur in order force to have communication. Each layer is often time refer to as a stack as well.
The open system, in a connection reference model, described the function of networking or telecommunications systems
independently from the underlying technology infrastructure, a devised data communication to seven abstract layers and standardize protocols and to appropriate groups up network and functionality to ensure interoperability with the communications systems, regardless of the technology type vendor and model.
Now, if you want to remember what these layers are, there's a simple way to do that. We can use an acronym call. Please do not go with the sauces. Peaches. If you go from layer number 1 to 7, that's high. Able to memorize the various layers of the US our model If you're going from layer number seven again from the application layer onto one,
all people seem to need data processing. Whichever one works for you,
because again, if you're going to sit down for the exam, you be expected memorized. The different layers of those are mounted. In fact, you remember what that various functions that occur within the various layers off the we call the stacks or layers, in other words,
so the physical layers response for the movement of individual bits. Other words. It takes eight bits to make one bite from one hot. Other words from one computer to the next.
So when you look at the physical layer, the physical layout, the S. Aymara defines connectors and interface specifications as Where's that medium? Other words stomach the cable with comets. We look at their electrical, mechanical, functional and procedural specifications provided for sending again these various bits screams on your computer network.
Mainly when you think about a repeating, the main purpose of repeater is, for example, when you're transmitting signals over long distance. What happens we have what we call continuation are the scent signals. Other words begins to, uh,
perhaps we call singer delegation. Other words. The signal's not as strong as it was when we initially sent it out,
and as a result of it, we need a repeater. So what the repeated does for us? In essence, it regenerates and retransmit that signal and function at the physical layer off the S R model,
and this next light again shows again something physical layer in terms of the bears come comparisons again. When we look it from the cabling all way down to the electrical properties, that kind of gives us information. Here's where so again, these are the components of the physical layer and includes these items here.
Now the physically includes the physical equipment involved in the data transfer, such as the cabling and switches. This is also the Leah what a data gets converted into what we call bit screen, which is a screen of ones and zeros. Ah, computer only understands ones and zeros. Other words, one being on an zero being off
the physical layout. Both devices must also agree on a signal.
Ah, convention so that one's can be the skimming from the zeros on both of these various devices. Now, within the physical lead we have on network interface card on the network interface card has a unique addresses burnt within Nick cart itself.
Next, let us now take a look at the data link layer. Now, this is they are two of us tomorrow, and what it does is allow the device to access a network to sin again and receive messages. It offers a physical address. So a device data can be sent to that network.
It works with the networking software when sending and receiving messages and improvise Aargh
detection capabilities. Now some common networking component that function that layer, too. You have your network interface card. You have your Ethernet and Tokyo means switches. You also have your bridges as well.
So at the data link, Clear is concerned with local delivery of frames between notes on the same level of the network, you have your Mac sub let which acts as the interface between the logical link control
and then your larger liquid layer. Let Nick control or layer is also known as a logically control as evidence from the name itself that for the data Linklater, the L L Layer serves the purpose are providing into inflow air control and multi plex and
different protocols over the Mac. Clear off the data link layer.
The data leaked Lynn's response for moving friends on one. Hop to the next. We have framing. We have physical address, and we have flow control. We have air control as well as access control.
So again we look at the data Letelier again, we have a unique address. Is burned into your network interface card by the manufacturer. No MIT cars have exact same address
you have. Six. He has a six bite address.
Again. The Mac address has a hardware dress, and also we have what we call our network interface card address as well.
Again, the data link layer gives the data bits to the neck Network interface card. It controls the Knicks, access to the media access or Mac. We also have care sense, multiple access, collision detection that occurs, and that good example will be with the new Ethernet. You also have your token ring again is example as well.
When you're looking at data link there, we have a term called Cycle It Redundancy Check. Now it's a technique used to take errors and digital data. You're CRC is ah, hash function that it takes a accident. Changes to Raul computer data, common use and digital telecommunication networks and storage devices such as your heart. This drives as well.
It's based on a barrier division. Also call again Pollo in the Miracle Cole. Check some as well.
Now we look at your media access control address again, basically gets advice. It has a unique identifier signed to your network interface controller towards your nick
again for your communication at the data link layer of your network segment. The Mac address is used as a network address for most are Tripoli. It'll to network technologies, including again are even that Aunt WiFi as well as our Bluetooth
now in review. The data lately is very similar to the network layer except the data Letelier. Facilitate data transfer between two devices on the same network.
Let's take a look at the switch. The switch in the context of networking is, ah, high speed device that receives incoming data package and redirect them to their destination on your look Aaron Network. A Lance, which operates at the data link layer on Layer two or the network layer off the ice Aymara and as such, has support all types of Pakis Porco.
Essentially, switches are the traffic. Cops are a simple local area network.
So again, we're looking at various network standards. Here we have again, the 100 based T is based on the physical layer, and so again we see some additional information on specs were guarding the network of standard,
but again brought then is based to the fact that all computers in the land of the words come on look, air network, they share the same channel frequency to transmit data in case. In this case, we told my 100 megahertz
the data link they used again for encoding DeCota and Logical organization of their data bits, data package or frame and address by the layer, which has gained two sub layers that we talked about earlier
allows for air free transmission or your physical layer or your local area network is, well, that elite layer sub. Blair is a logical link clear. It manages a row checking and data flow over your network.
Some additional information regarding switches is the most common type of switch used on the land.
Again, it switches on hardware base and use a Mac address as well.
Obviously, a reporter switches map to a specific Mac address off the computer that physically can next to it.
We also use switches for bee lands, allows it create a virtual lands original logical group in the work station service, and their devices appear to be on the same land. Ah, good purpose for this is for security purposes, where you would set up the land and the only device you can separate land. What is a switch?
We reached a post assessment course in here which led Always I'm outta includes Phelan isn't a physical, is it? Be data link. Is it C network or the D transport?
If you said, like again data link, you're absolutely correct now doing. Of course it's presentation. We discussed the physical layer as well as a data link layer.
An upcoming presentation will be the focus of attention upon Layer three, which is the network layer.