Computer Jobs Blog

The term 'storage devices' can be applied to any type of memory that stores data - temporarily or in a more non-volatile capacity. This memory can range from off-site tape backup devices to CPU caches.

The context in which Sybex treat storage devices for this part of the A+ essentials syllabus is one of secondary memory - or 'non-volatile' memory. In short- any device you can save data to, power the computer off, then back on again and find it still there.

So CPU registers and RAM chips aside lets take the term storage devices to mean things like;- Hard disks, floppy disks, CDs, DVDs, USB memory sticks, compaq flash cards, tapes and anything else that doesn't store data in a temporary or 'volatile' way (volatile meaning the data is lost if the computer loses power).

Another distinction to make here is that volatile memory stores data in memory address space which can be accessed randomly unlike non-volatile storage which uses a file system to organise it's data.

Now that's out of the way it's time to look at the different types of data storage available and their respective differences, each one will be covered in more detail in upcoming posts:

• Hard Disk Drives - magnetic storage, data stored sequentially. Can be partitioned into many different drives or spanned together into large volumes. Connect via IDE, EIDE and SCSI interfaces. Can also connect externally via USB.
  
  
• Floppy disks - magnetic storage, thin disk in plastic casing. The only size in use today is 1.44 MB, still have some use as bootable disks for OS installations, imaging boot disks, anti virus emergency boot disks and other emergency boot disks. Most new PCs these days do not ship with floppy disks drives. Connect through IDE interface.
  
  
• CD ROM/R/RW - optical storage. External, slower but very portable. Can be read only (ROM) and writable. Capacity of around 650-700 MB (sometimes more). Can be IDE, EIDE and SCSI as well as external via USB.
  
  
• DVD ROM - Optical storage - higher capacity than CD ROM and can go up to 17 GB (double sided) but typically 1.6 GB. Can be IDE, EIDE and SCSI as well as external via USB.
  
  
• Zip drives and jazz drives - Detachable external hard disks (magnetic storage) holding up to 2 GB of data (1 for zip 2 for jazz). Connect via parallel.
  
  
• Tape drives - Magnetic storage. Once used instead of floppies and CDs - tape drives store a lot of data but are very slow to access the data. Now only really used for backup and archiving.
  
  
• Flash drives and SD cards - very popular for easily transporting data, taken over from floppy, zip and jazz drives. Many of the emergency boot functions of floppy disks can now be performed by USB flash drives. This type of storage is also used in other devices such as digital cameras and MP3 players. Advanced techniques enable a memory chip to be written to and the data stored when there is no power to the drive.
  
  Flash memory boasts very fast access speeds compared to other non volatile storage although drawbacks include limitations in rewriting such as number of rewrites supported. It is also more expensive than hard disk storage although becoming cheaper.

So there you have a mile high overview of non-volatile storage devices. Stay tuned for more detailed posts on each one and the different technologies they employ. If I've left anything out or made any mistakes please post a comment.

I think I'll go to bed now - good night!

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)

January 4, 2007 17:43 - Last day buy 1 get 1 free SBI! frenzy is upon us! Become an entrepreneur today

Well just as we thought Christmas was over and life had returned to normal Sitesell went and pushed it on another day!

Of all my New Years resolutions this year the only one I will hang on to for sure is to build my entrepreneurial business to the point where I work for myself full time.

We've heard it all so many times and see the whole 'make money online'/get rich quick' nonsense touted all over the place. SBI! is about building a business, a real long term business that takes work, patience and dedication.

It's definitely NOT for any instant gratification, easy street, 'make money by doing nothing - sit back while it all just rolls in autopilot' seekers. I'd love to know how many people those - secret ebooks - actually work for anyhow.

Visit any popular internet marketing forum and you'll see how hard it is, how many people struggle with the learning curve, and how many people give up saying it doesn't work.

It does work- it's just damned hard work, and when the ball is rolling it's sweet sweet sweet! I write this as I just received a 'congratulations another sale' ($150 which will recur every year on this day as long as my customer renews - which they will!) email.

Passive income absolutely rocks, the hard work is so worth it when you see it pay you back. Fitting in the amount of learning and doing around a 9-5 is exhausting, not everyone can do it and stay focused and motivated - particularly when you're not seeing any results.

But isn't that what defines a true entrepreneur?

-Relentlessly pursuing their goal in a strategic way. Focusing on success and weathering all the storms. Sacrificing free time, leisure and relaxation. Swapping instant gratification for an understanding that true long term success will come as long as the process is followed patiently. Testing and tracking results to find what works for YOU and what doesn't. Being flexible in your approach and prepared to make necessary changes to improve chances of success.

It's a far cry from clicking an ad on the right side of a search engine saying "I make $x amount a month doing diddly squat - buy my secret system and you can be doing the same today- quit your job tomorrow!"

Instant gratification is for mooches. What's a mooch? - As defined in Ken Evoy's blog a mooch is someone who buys GRQ (get rich quick) program after GRQ program looking for the golden goose that doesn't exist.

If you think you have what it takes to become a true entrepreneur and build a long term solid successful business online then check out Site Build it! - the buy 1 get 1 free ends today - 4th January! -

A word of warning though…. It's not for mooches!

Here's to a new life in 2007, mine is already well underway! Cheers!

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)

January 10, 2007 12:23 - A+ Essentials Domain 1 - PC Components - Magnetic Storage

Going back as far as 1898 magnetic storage has been used to capture analogue and more recently digital data. The most common forms of magnetic storage devices are tape, disk and strip.

Common characteristics of magnetic storage are that it is non-volatile, very recyclable (can be written to and overwritten a lot), the data is stored sequentially and accessed by a read/write head.

The most used magnetic storage devices today are hard disks and tapes. Both can support high volumes of data and fairly decent access speeds (not so much for tapes).

There is still a use for magnetic tape for storing analogue audio and video, although digital mediums are taking the place of analogue - analogue music will always have a special place in my heart :)

Floppy disks also use magnetic storage which can easily be rendered completely useless by placing a mobile (cell) phone on top of them resulting in being verbally abused by an irate colleague for wiping "the only bloody boot disk we've got for that ***ing machine you ****!!"

For the A+ the main types of magnetic storage you need concern yourself with are hard disks and tapes. There is a qute exciting new technology emerging known as magnetic RAM or MRAM - if interested you can read more about that here.

It has also been suggested that advances in flash memory could one day replace the need for hard disks but at the moment it is still more expensive (although coming down in price) and has limitations on the number or re-writes it can support which throws doubts over whether it can run operating systems or not.

For some more in depth information on magnetic storage have a look at these articles on magnetic disks and magnetic tapes.

For the forseeable future hard disks will be used as primary storage due to speed and writability restrictions of other types of storage media. Tapes are very suited to backing up and archiving of data and floppies... well all I'll say is just watch where you put your phone.

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)

January 21, 2007 20:19 - Proactively Furthering Your Own Career

When I started my new job the first thing I wanted to do was leave. The state of the office was awful, the carpet was (and still is) absolutely disgusting, the comms room was a mess with old boxes, tapes, 10 year old kit lying around and don't get me started on the patch panels..

This was some culture shock coming from a very innovative, forward thinking pharmaceutical company where everything was immaculately ordered, spotlessly clean and tidy and all the technology was brand new with that 'just out of the box' polystyrene smell about it.

Then there was the documentation, SOPs, WSOPs, change control procedures, documentation, and general recording of everything in order to comply with regulating authorities and client audits. This stuff makes Sarbanes Oxley look like a classroom full of 8 year olds with access to unlimited paints and no teacher for a good hour or so.

My new environment couldn't be further on the other end of the scale. Yeah we have SOX compliance (those 'say what you do - do what you say - prove what you do' posters all over the place) but on the whole - for a multibillion international giant of a company one would expect a bit more innovation than there is.

But like any successful business money is not spent for the sake of it and there's that old saying "if it ain't broke don't try to fix it!". However - waiting until a critical system finally falls over for that last time before replacing it is a bit of a false economy.

Faced with such a situation one can choose one of two courses of action - run away as fast as possible, go tail between legs back to the old job - or

Try and turn it round.

I've chosen to try and turn it around. Even though it is a huge organisation that is very set in its ways they seem prepared to take on fresh perspective to swim as opposed to sink.

Trying to turn this place round will be one huge uphill struggle, but that's half the fun - right?

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)

January 22, 2007 21:16 - A+ Essentials Domain 1 - PC Components - Hard Disks

Hard disks are typically kept permanently inside the computer in the case of PCs and workstations. Some servers have visible disk arrays which support hot swappable disks for easy replacement and adding more drives to an array.

Hard disks use magnetic storage and read/write heads. They typically consist of the disk itself, a controller and a host adaptor. They can interface with the computer's motherboard via IDE, EIDE, ATA, SCSI and more recently SATA.

SCSI supports very fast read/write access and can have up to 15 devices on a single controller. Each device is assigned a SCSI ID starting from 0. SCSI is expensive and used mostly in servers.

PC/workstation hard disk drives typically connect via IDE/EIDE and SATA. IDE devices (Hard drives, other drives such as CD/DVD drives) can go 2 to a controller and need to be configured as master and slave unless they support cable select which will autodetect which is which. These settings can be manually configured with jumpers that are usually found around the area where the power cable and data cables attach to the drive.

Adding an extra internal hard disk drive has its benefits of giving more disk space but it can slow down performance and add extra heat to the inside of the machine.

Hard disk size capacities are constantly growing as are space requirements of ever evolving technology.

Hard disks can be partitioned into lots of little chunks that act as separate virtual drives even though they are on the same drive - or they can be spanned together into large volumes.

They can mirror each other (RAID 0, RAID 1) for fault tolerance or be configured in RAID 5 (redundant array of inexpensive disks) which spans the disks together into a larger volume and also creates a parity which in the event of a disk failure it can be replaced and the RAID array rebuilds itself with all the data intact (hope I explained that well enough! - if not sorry - here's more info).

*Real life tip - if a drive is causing a lot of errors and starts to make a *tick* *tick* *tick* sound - get the data off it ASAP - get Outlook PST files first if they live on the drive these are always by far the most important files a user could lose.

Well there's a lot more to hard disk drives than that, for more info you can read this.

I hope you've enjoyed reading this post as much as I've enjoyed writing it - good night!

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)

January 26, 2007 17:55 - Pull your SOX up!

Is your company SOX compliant? Are you familiar with SOX and how it affects you, your IT department and your accounting department?

SOX - or Sarbanes Oxley for those of you who don't already know about it was brought I after the Enron scandal to keep tabs on public companies, their accounting and IT systems so as to stamp out any future bad behaviour.

As a result all kinds of rules and regulations now apply that affect the way IT employees right down to the helpdesk and 1st line.

Things like getting users to tell you their password so you can log in as them and configure their profile on a new or re-imaged machine are now taboo. "No you can't have my password it's a SOX violation!" I learnt just the other day.

I'm still finding out what else I can and can't do because in my company so far there is no official SOX training for IT, I just get little rules quoted at me as and when I attempt to break them.

Looking on the Sarbanes Oxley website I find little available info without having to create an account and log in which I don't really fancy right now. However there is some useful quick info about it here and even a forum here.

Whether we like it or not (and it's apparent that a lot of CEOs, CFO's and heads of IT are in the 'not' club) SOX is big, it's here and it's not going to get away. If you work for or are thinking of going to work at a large US company that's listed on the stock exchange you're gonna have to learn to pull your SOX up!

This strikes me as not a bad thing for the fresh faced IT entry level applicant. Do you really want to stand out from your competition? What if you could put "SOX certified" on your resume and cover letter? I bet that would raise a few eyebrows.

If only there was a SOX certification track… Well luckily for you there is!

Click here for more on this subject

To reference this entry please copy the url in this link: (Permalink)