>> Hey, everybody. Welcome back to the course.
So the last video, we wrapped up our discussion on
the different phases of investigation in Module 2.
Here in Module 3, we're going to go over
some generalized information about
hard disk and file systems.
In this video, we're going to start talking
about the different components
>> that make up a hard disk.
>> A quick pre-assessment question,
what is SSD stand for?
We'll learn that in this video.
If you guessed Solid State Drive,
you are correct, that's what it stands for.
The other ones are pretty obvious that they're made up.
Hard disk driver or HDD,
this uses magnetic storage to store and retrieve data.
It's also non-volatile storage
because of the magnetic aspect of it.
Some components of it are platters,
tracks, sectors, and clusters.
We'll talk about those a little bit.
Platters are going to be the circular metal disk
that are mounted in the drive enclosure.
Something important for the exam you want to
remember is that there's two heads per platter.
Just keep that in mind just in case
you see some questions on platters for the exam.
Tracks. This is going to be
a concentric ring on a platter.
We've got a little image there.
For the CHFI examination,
you're not going to be questioned as far as like,
what's the difference between a
geometrical sector and a track sector,
it's just going to be basically like a track.
It's going to be listed as a track or track sector.
These contain disk blocks
and they store data in this numbering is 0-1,023.
That's something else you'll just want to keep in
mind as you are studying for the CHFI exam.
Sectors are going to be the smallest physical storage
on the hard disk platter.
These are 512 bytes long.
Now 512 byte,
you'll also notice that's a master boot record as well.
Just keep that in mind, you might see that number on
the exam tested in some capacity.
We also have things like bad sectors.
Another topic that's in the official EC council material
that might be on the exam.
Basically, this is as it sounds.
It's portions of the disks that are unusable.
Could be due to flaws.
Generally it's caused by configuration issues,
and it could also be caused by
the physical disturbance to the actual disk.
The Master Boot Record, as I mentioned, 512 bytes.
That last portion is very important there,
that's the signature so that 0xAA55.
You'll definitely want to memorize that just in
case you see something about it
on the actual examination itself.
Clusters we mentioned,
these are the smallest accessible logical storage units
on the hard disk drive.
These are formed by combining
>> different sectors together.
>> Slack space. Basically,
as the name implies,
it's a wasted area.
Think of like that slacker person.
They're kind of a waste of the human body.
They don't really do anything. They sit on
the couch all day, that sort of stuff.
Similar thing here in that aspect,
of it's a wasted area of the disk clusters.
Basically we've got small files or we're using
small files and from
the end of that file to the end of the cluster,
that's going to be the slack space.
That's that wasted space.
SSD or Solid State Drive,
which is more common,
or at least in certain devices,
a more common thing that you see nowadays.
These have some advantages.
Higher data transfer rates,
the area storage on them,
the storage ability, reliability.
They're are also non-volatile,
but they come with a price.
They cost a little more than HDDs.
Hard disk interfaces.
Realistically, you probably won't see this
on the CHFI exam.
It is mentioned in the material,
but I doubt just because this is somewhat older stuff,
I doubt that you would
honestly see that on the real exam.
But again, you could. It's good to
notice what these are if you're not familiar.
This is more along the lines of kind
of like A plus type of knowledge.
Your SATA, your PATA,
and then, of course, your SCSI as well.
Just a quick pulse assessment question here.
True or false here that the MBR or
the Master Boot Record that it's 512 bytes?
Is that true or false?
That's true. You got that correct if you guessed true.
Again, that's something
that you'll just want to memorize as
you're studying for the CHFI examination.
In this video, we just went over some of
the components of a hard disk.
We also talked about SSD
and what that was or Solid State Drive.
If you remember, the pre-assessment question
was regarding what does SSD stand for?
The next video, we're going to go over some things
like bit vs byte versus nibble,
as well as some other topics that are related.
Again, in this entire module,
we're just going over the structure
of hard disk as well as file system.
A lot of memorization,
if you will, on these
particular things that you'll need to know.
But just make sure you understand
them that way as you see
the terminology on the examination, you'll understand.
For example, if they tested you on Master Boot Record,
you would know that that's 512 bytes and you would know
that MBR stands for Master Boot Record.
Just keep all that in mind. This is like
foundational knowledge that you'll need to know.
Number 1 for a career forensics,
but also more so towards the CHFI examination.