There's a lot of pretty basic questions on the exam that cover information that well in my opinion if
your at this level of study you should know everything I'm about to talk about but for completeness
and because they are listed as objectives let's go ahead and go through these.
First of all what I want to talk about is IP address.
Now there are two different types of IP addressing they're being used today.
There's the old school IPV for me.
Here's an example of IPV 4.
You'll notice that we have 4 octets separated by three dots.
Each of these octets is actually eight binary values.
So there are four of these.
So four times 8.
This is a 32 bit address IPV 4 has been around for a long long time and it looks to be around for a
little bit longer however other stuff is coming.
Now what we talk about IPV for addresses there are certain addresses that you need to be able to recognize
instantaneously.
And these are known as the private IP addresses.
If you're going to put a computer on the Internet you're going to have to have a legitimate public IP
address handed to you indirectly from IANAL.
So usually what happens are local ISP gives us those addresses.
However if you have a private local area network and everybody's just using web browsers and such it's
common for us to separate this router from the real Internet through what's known as natural address
translation ordinate.
And what we're going to do is then we're going to use private IP addresses so you need to recognize
private IP address ranges so let's go ahead knock them all out first any IP address that starts with
the number 10 is a private IP address.
Second any IP address that goes from 172 16 to 172 31 is a private IP address.
And third anything that starts with 192 168.
The third value is up to you but there has to be a third value in this case.
These are also private IP addresses and I hope you recognize these.
OK.
That's pretty much all I want to cover for IPV for IPV 6 has been around for a number of years but it's
only in the last few years and it started to become common.
If you run an IP config on your system check the IP address you'll see that you might find an address
that looks something like this.
An IPV 6 address is broken up into eight of these four digit chunks and notice some letters are used
here because this is hexadecimal as well.
So if you take a look at this entire address it actually goes up to 128 bit so and IPV six addresses
much bigger than an IP before address.
Now if you were to look on your system you'll notice that you often have two or more IP D6 addresses.
First you're going to have your link local link.
Locals are easy to identify because they always start with F E 8 0 link locals are generated automatically
by individual hosts then you're going to have some type of Internet address.
They often will have numbers that start in the 2000s range.
So here's an example of an Internet IP V-6 address.
So it's very common within the IP V-6 world to have more than one IP address where with IP before you're
only going to have one address.
All right.
So make sure you're comfortable with IPV for versus IPV 6.
Now the next thing I want to talk about is when we talk about when we use the word TCAP IP that's really
kind of a lie because really what we're talking about is we have a number of transport protocols we
have TCAP we have UDP and we have ICMP.
So let's take a moment and talk about these three.
First of all TZP TZP does most of the work on the Internet.
And that's why we call it TCAP over IP and not TCAP and UDP and ICMP over IP TZP is a connection oriented
type of protocol in a TCAP what will happen.
I'll have two ends of a connection.
So once a client runs a server what will happen is the client will first send a hello message.
Then the server will send back yes I got it.
And then the client will then send his message.
And that what we call the three way handshake is the corner stone of TZP now TZP has some really really
important aspects to it.
Number one it's connection oriented we always have to start with this connection.
And number two you can have lots and lots and lots of packets being sent and that's why you will see
for things like web pages and for email and stuff like that pretty much everybody uses TCAP.
But there are two other protocols.
The next one is called UDP.
Now UDP is a lot different than TZP number one UDP is connection.
So if I've got a client and I've got a server somebody just sends a message in hopes that the other
person gets it so there no acknowledgement to it.
The other thing about UDP those you can send lots and lots of packets.
So UDP is used in situations where you have a high degree of confidence that the other person's listening
the last one is ICMP ICMP doesn't really run at the same level as TZP and UDP.
But it kind of lives in the same world so we tend to put it there.
So ICMP is like the maintenance worker of TCAP IP networks ICMP main job is to handle the little important
but boring things for example are messages and pings and all that stuff run under ICMP ICMP is always
going to have just one packet doing whatever it's going to do.
And that's pretty much all there is to it.
All right.
So for the exam make sure you know IPV for IPV 6 TZP UDP and ICMP.