Welcome back everyone.
Now we're going into a full fledged Internet layer protocol or or and network access.
Right.
The IP protocol.
All right.
Consider this a connection less routing for recall.
There's two main reasons for this particular protocol.
OK routing one and providing a single network interface of the Aubert layers.
It can talk to the other leaders why without this layer application programmers would need imagine this
would need to write what's called hooks into every one of their applications Rej different access Oracle
owl.
So you're trying to do anything to get to any other protocol.
There's other I we were just talking about and this guy I.P didn't exist.
You need to actually buy it somehow.
OK.
So it's ok.
IP provides on a single network interface.
The oberlé are portable that says they turn on the IP protocol IP for an IP address it's on them.
We'll be talking about that.
We'll we're talking about that.
And while things are running in with this protocol obviously IP ICMP we all know that if you don't use
the protocol that we use when we paying OK.
Now why do we pay.
Funny story I guess one ground use for it.
But how does one student one time tell me yes I may I make sure that all Linux Unix servers have communication.
I'm on one.
How do you do that.
Well I'll make sure that information get across.
OK when you do that how do you get.
How do you know that communications getting across what you use.
What software application what me although I paid.
And I said Olson paying for a I shouldn't have said that but I would say OK.
But yes pinging is ICMP and that lets you know hey he's alive.
I mean any and you can pay somebody great you have connectivity to it might not be able to get to a
share.
Why not be able to resolve host name not be able to do many other things.
Ok so I you are going to do any we or one out now only to see if there is any other problems we need
to get into that.
And are they all is this an APB for our address resolution protocol.
There's no reverse or are going.
Well there is but more about it.
OK.
Adverse resolution protocol.
All right.
This is exactly what happened the first time.
You all should know this or you better know this.
I want to tell you now we don't.
OK.
Well first time that you tried to get anywhere OK it's within your own network there's going to be an
art request sent out.
Right.
The switch is going to say oh my god i have our broadcast coming towards me.
Who is that MAC address and puts it in his sport.
I have a destination.
Well I don't know the MAC address.
Hey everybody who is the owner of this IP I can you get the backorders what's in an upward.
It was in the same segment right.
And then now you have these two MAC addresses on either Portuguese.
Let's go back and forth anymore our broadcast with a special type of broadcasts.
Right.
It was trying to get outside your network.
Are you all with a router you know to send an R to the router.
The routers want the interface that you're connected to that need your MAC address.
Oh OK let me give it to you.
I got it.
I had the Agadir.
I completed it.
I now know my.
I know my IP.
I know that I know my math.
I know my defog that way.
I know the destination.
Don't want to go to.
OK.
Ivy or name where will I be.
All right.
But I don't have the destination MAC.
That's why I need to do an arm.
I can have it.
So that is important.
Art is important.
It existed that before I say does not exist do not block it.
Would you block ICMP V-6 you run into issues that simply B-6 or.
Is the one it has a heck of a job.
The girls and I and IPV say we have neighbors solicitations Mayberg knowledge minutes Laura's hallucinations
rodder acknowledgement.
We have had up to address the Taschen OK.
If you block ICMP there goes IPV says don't do it.
All right.
Anyway so this is what the protocols are run within the IP protocol.
I prefer not to understand that IP looks at each packet address then using a roundtable all.
Now we're getting into some fun stuff or writing table inside where a packet is to be sent next choosing
the best sended upon.
How is our writing table made.
OK.
Going That's not to say I PVC's segments from the host player and fragments them into datagrams necessary
i.p then reassemble undergrounds back into segments on the receiving side.
Remember sequencing when doing we really back together was assigned the IP address of the sender and
that of the recipient.
The right decision is based on the Pagar destination or is based on this and they should rest obviously.
OK.
Or this writing.
Things based on routing thing.
OK.
Well that means you know you better know 100 hour how are you writing or using the four hours or using
static routes are using our routing particle.
So just rip on that rivers and obviously please reversion to revenge.
By far I believe six were using the European or European or version 6 or using OSPF or SPia Burgundy
are using I asked are we using BGP be.
Where are we using.
OK.
Sabata wrong Pericles or we want to use.
OK.
So the painting apparently on around the corner call is depending on that type of writing table and
depending on the algorithm when there are a protocol in which way it's going to send it.
So that's why I say this is a four letter OK because when everything gets there as you go around it
you don't have to talk to.
I mean you want to lead your network don't you.
You want to stay home all the time.
You want to venture out there right.
You want some packets across the world.
So routing very important
order calls the ICMP really says one.
It's not a real protocol.
Number one is a request or a reply.
Ok yeah I've been I've e-tolling that's for TZP a six unit UniFi 17 is European.
Eighty eight or 89.
These are again Kurkov for recall numbers.
Now port numbers protocol numbers what they did was they like wireshark.
Usually something like this.
OK.
Or SPF 89 EPB 6:41 you're a 47 and Lehre tutorial to T-P is 115.
Any kind of security that you're doing in there.
Again should you know this.
Yeah.
OK.
Yeah you should.
You learn the basics.
But you know TZP UDP Europea your multi.
You're writing protocols the nature Ah but understand that these are protocol numbers.
And it's very important really to me.
Yes.
When we were looking as some sort of network analysis tool or I said all optical are 88 What have you.
OK we're working with this particular route.
We know we're running for global warming with be configured all day.
So you know what it's going to say or be everywheres going to say whatever or yeah you ropy say whatever.
OK so again these are just protocols with their numbers that work.
And this particular earlier.
But the important thing to remember the Internet layer IP protocol is connection less.
This is where the routing is the meat and potatoes right here.
Routeing riggings where import emetics.