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Friday 20 February 2015

Storage Devices - Part 2 


1 Watch the video  and put the words into the gaps in the text


If you took each one of the (1)___ and you separated that into smaller pieces, you’d have these tiny little pieces called (2)___. Each sector on a drive is five hundred and twelve (3)___, not a lot of information is stored on a sector, and you could see it’s also a geometric type of problem because if you’re on the (4)___ ring, you’ll be able to have more sectors on the outside ring than you have on the inside.  So it’s not like cutting a pie, you really have a different number depending on the where you are, on which track on the drive.
Also keep in mind that you could fit on these larger hard drives, you can have a lot of sectors, you could have millions of sectors on a drive, and you get into a (5)___ problem of how is the operating system going to keep track of all those tiny little pieces on the drive. And the way we’ve address that is we have the operating system put many of the sectors together into what we call a ‘(6)___’.  We cluster the sectors together and your operating system depending on the type of (7)___ that it uses, the type of file system on there, may have different sizes of clusters. That might be a 1(8)___ cluster, it might be a 64K cluster. In TFS depending on the size of the drive might be a 4K cluster. You’d have to look at the ‘Check Disk’ command on your computer to tell you what is the (9)___ of space on a cluster on this particular drive that I have. Each drive in your system may have a different cluster setting depending on how big the drive is and the type of formatting done on the file system. But it’s just a way that I can now group together the different sectors and now it’s easier to (10)___ of them because there are fewer number of clusters ’cause I’ve  taken all those millions of sectors and now got them into something that’s a little more (11)____ for my operating system.
When you’re working with a hard drive it has to know where to start the system, it does something, uses something called a ‘(12)___’ to do that, an MBR. This is usually the first sector of the hard drive; it is 512 bytes just like we’ve mentioned those sectors are usually that size. And inside that tiny little sector has a table of primary (13)___, there’s a disk (14)___ that’s used so that your operating system knows which disk that is, and there’re (15)___ on where   you should go to start the operating system on this hard drive. And so there’s a lot of great information but obviously that’s a pretty important (16)___ record. That one sector on your hard drive contains a lot of important information, without the MBR you wouldn’t know how to start operating systems on this drive and whenever you have a problem with your master boot record your system doesn’t do it, that’s why. You usually have to rewrite your master boot record so that it now knows where to go on the drive to get the information it needs to then start the operating system. When working with hard drives and storage interfaces you’ll see different kinds of interfaces that devices will (17)___ into. This one at the top SATA, the Serial Advanced Technology attachment, one of the most common these days,  it’s very high-speed interface, it’s become one the most popular interfaces to use to plug in hard drives and other components as well. In older machines you may see something called PATA, Parallel AT Attachment, we used to call it ATA, before there was a Serial ATA there was a Parallel ATA and since that was the only one ATA that was we just call it ATA.
There was also an adjunct to that called AT Attachment with Packet Interface. We did that so we could plug in other devices that weren’t necessarily hard drives. Those SATA and PATA interfaces were really designed for hard drives but we also had things like CD-ROMs and DVD-ROMs and we are able to take advantage of that by using a (18)___ interface but a different type of protocol in use called AT Attachment with Packet Interface and we were able to plug in our CD-ROM drives using really the same drive controllers as a PATA. But we are now able plug it right in and use it as if it was sort of like accessing a hard drive except it was a completely different type of piece of (19)____. There is also something called Integrated Drive Electronics. This is what we originally called that PATA format, it was the original standard created by Western Digital and when we updated that original standard to something newer it was more of the (20)____ parallel AT Attachment is what we call that. See me here, IDE and ATA used in similar forms in fact on order drives that actually may be marked IDE or ATA it’s really (21)____ to exactly the same thing. And although it's not mentioned specifically in the new A+ certification requirements I put on here because you might see it something called SCSI which is the Small Computer Systems Interface. The use of SCSI is (22)____ away now that SATA has really become one of the primary methods of connecting drives in our computers, our laptops, our home computers, and even our enterprise file systems and file servers. But SCSI is still around, you’ll see older computers and even some of the existing computers today with SCSI drives and SCSI interfaces there. So if you see that SCSI, we call it ‘scuzzy’, it is just another format of plugging in different kinds of drives so that we can access those drives through different controllers on our systems. It has a different type of formatting, uses different interfaces just like all of these do, but there’s something else that you’re going to see when you start plugging in different hard drives.
Of course there are not just hard drives to think about these days. There’re other types of media that use light, they use lasers, and these optical formats are important as well. One that has been around for a long time is something called compact disc, CD format. Generally you fit about 700 MB of data on a single compact disc and it’s a format that we still used today for lots of types but 700 meg these days isn’t a lot, it’s good for taking data and sending it to other people, maybe having programs that we would buy to get into our computer but there’s not a lot of space relatively speaking to other formats we have these days. (23)___ a DVD, which stands for Digital Versatile Disk, I can fit for a single layer DVD 4.7 gigs, that really extends my (24)___. If it’s a (25)____ DVD -  8.5 GB of data that I can store on a single piece of media. And that is really a lot more than the CD. In fact what we see in the latest machines generally is this DVD format, but there is a new format on the block and that is a Blu-ray disc. And you can see it’s obviously much bigger than the CD or the DVD on a single layer Blu-ray 25gig, on the dual layer Blu-ray 50 gig of space available on that single media.  Now they all look very similar, this is a Blu- ray disc, they all look about the same size but obviously are very different in the way the data is stored, very different formats and how we are able to take that data. So going from 700 megabytes now all the way up to 50 gig, Blu-ray these days is still relatively expensive on the media and the drives themselves but those numbers are dropping quite rapidly and pretty soon it probably will be very common that everybody’s just going to have a Blu-ray disc inside of their computer. And that’s what we’ll use to read and write these different formats.

outside
tracks
bytes
sectors





K

logistical


formatting

amount

cluster

manageable

keep track




signature

partitions
plug
directions
boot
master boot record


















generic
equipment
referring
dwindling
similar





















capabilities

dual layer

For instance






2 Vocabulary focus. Sudy the words and  word combinations, practise their translation, spelling. Check your knowledge in the test. Play vocabulary game and set your own vocabulary game record.

3 Mark the following statements as True or False

 1. Tracks are the small pieces the sectors are subdivided into.
2. The number of sectors on every ring of the disc is the same.
3. Sectors are put together in clusters that may be from 1 K to 64K.
4. “Check disc” command shows how many tracks you have on your disk.
5. MBR is the first sector on the hard drive.
6. Whenever you have a problem with your master boot record your system doesn’t start.
7. SATA stands for Parallel AT Attachment.
8. SATA and PATA interfaces were designed for CD-ROMs and DVD-ROMs.
9. You fit about 700 GB of data on a single compact disc.
10. On a single layer Blu-ray you can fit 25GB.
11. Blu-ray is still relatively expensive.

4 Answer the Questions
1. What are tracks and sectors like? How can we manage a large number of sectors?
2. What is ‘cluster’?
3. What is master boot record? What is its function in the system? How can we fix problems with MBR?
4. What types of interfaces do you know? Which is the most common and which is the least common?
5. What kind of devices can work with those interfaces?
6. What types of optical storage devices do you know? What is their capacity?
7. What advantages and disadvantages do CDs, DVDs and Blu-ray discs have?

  5 Matchmaker: match key computing terms to their definitions.

 6 Matchmaker: Match the descriptions and typical uses to the device.

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