Hello and welcome back to I C and D one interconnecting Cisco Networking devices. Part one
this is Episode 113 T C I p layers.
I am trending Darryl and I'm gonna be the instructor for your course.
The last video we went over some information and history about the TCP I p model. In this episode, we'll be covering the TCP model layers all the way from the application layer to the physical air
learning objectives of this episode. We're gonna learn the layers of the TCP I p model.
She's gonna be the application layer transport layer,
And in the Linklater, we're gonna continue with the original RFC standard that it combines a day Lincoln physical layer
So quick, pre assessment before begin.
At which layer does air recovery happening? T c p I P stack,
I'll give you a few seconds here, toe. Go ahead and research this and see being find the answer.
Look, I hope we found the answer now, and hopefully you got it right. It is the transport layer and we'll be talking about that in just a little bit here.
So first off, we're gonna hit up the application layer, which is the top layer of T C P I P. Stack.
What this is going to do is this gonna provide the service is to the user applications.
So what it does is it defines the protocols and service is the applications will actually used. So the biggest one is gonna be http or the hypertext transfer protocol.
So what happened here is whenever your Web browser,
like, requests a web page from website,
but it does. It sends a request out to a server,
and the server's gonna go ahead and send back that way, Paige,
and you're gonna get a status code 200 in case you're curious.
But what it does is actually defines on how your computer asked the Web server
to receive that Web page. Something if you're talking S S h D N s. It defines how all those service is
Next, we're gonna look at the transport layer. So here were mainly focused on a TCP and Judy P protocols.
TCP you're gonna see a top here,
and Judy P is down here.
So TCP The biggest thing is this connection based. So what you have is a three way handshake. You have a sin
sent from your computer to, let's say, a server
the serval son back a sin AC
or synchronization Acknowledgment.
And then you will send back a acknowledgement completing the handshake
and what it does. This is the one that's gonna focus on a recovery. So TCP and the transport layer does a recovery. Like we said in the beginning.
And how it does this is with these sequence numbers
and the acknowledgment numbers.
So let's say you have three packets that it's up to you from the servers and say 123 and you only receive one of three. What you're gonna do is request packet number two back from the server.
So in UDP, this one is actually connection connection list. So we do not have a
handshake. And this one this one, it just has your ports
and later on at the I P address, but
and it just kind of sends it out, and if it gets there, it gets there. So this one is very good for multimedia streaming.
You see it because if you try to use TCP for that, it would There were the amount of band with it would consume.
We'll just be too great. So this one, Do you see a lot of streaming applications?
So where if you lose, you know, millisecond of video or audio? It's not a huge deal. It's not too bad.
But let's say you only get
80% of a website that could, you know, that's gonna mess with everything. Everything, you know, I was a garbled.
It's not gonna look good. So they have their applications or uses in both places.
Next, we look at the Internet later, so here we're actually looking at
the think of a post office, right? So think of an I. P. Is a address that you would have your house.
So is a unique address generally that will identify your house.
What it also does is the post office will use was a zip codes for the United States as a way to rout these packer these letters.
So what it does it takes, you know, post office, eh? It goes to, you know, be
and let's say he goes down here,
you know, it takes this wild route, so be able to delivery here
Letter to the next person. So that's what this does is let's say
your packet is here.
It needs to go all the way over here.
The routers know what route to take to get it over there
by using the I. P. S. So you have two different version. You have I p version foreign I p Virgin six I've been version for is the 32 bits one that you generally see. You know, the 1 91 681.1 stuff like that
and then I p six is the kind of honestly crazy looking one that we'll be going over later.
Next is the Linklater. What it does is in a capitalist. The i p pack it into a frame.
And what does that adds a Ethan a header and trailer onto the outsides of the I P packet.
And then from there, transmits over the physical lines or other media being a wife, I say, in the form of bits so ones and zeros.
So this will include standards like a toe to toe three,
which is the Ethernet like physical standards. 802 Down 11. When the WiFi on the point of point protocol
and also, you see on the right, there's quite a few more like Why, Max? Bluetooth Token boss frame relay.
So kind of the steps of data encapsulation is kind of what I talk about in the course intro when I said Think about what is happening
of encapsulation. So first the application's gonna kind of create the data.
We gotta determine a protocol to use,
and then it's gonna go to the transport layer from there is going to decide, you know, depending on the application protocol is using what it wants to use T c p R u t p.
I was gonna add on the header there.
Next, the Internet layer is going to catch elated by putting out an I P headed on there with the destination and the source i p.
well encapsulated what frame header trailer footer.
And then what? You don't seem a picture. There's where it converts it to bits and sends it over the different standards. Ethernet, WiFi. Why, Max Blue, too, is something like that.
So quick post assessment here to make sure that you know, we're grasping everything. So which TCP I layered deals with the routing of a packet
again. Think of the post office example. See if you can remember
again. I'll give you a few seconds to pause the video.
Okay? Hopefully, you figured it out and you got the same answers Me, which is the Internet layer. Remember, that's the one that includes the I P addresses and includes the ability for routing now.
So in the next episode, with me going over the OS I model, which kind of
isn't used now logically, But we kind of a lot of times we were late, everything to the different layers, and they all signed model.
And once again, if you guys have questions, need help. Or if you have some funny computer fixed pictures,
go ahead and send me a message like you haven't
I look forward to seeing you in the next episode?