CTO Tech Blog

Have you ever gone to a store to buy blank recording media and wondered what all the letters and symbols mean?   I decided that it might be interesting to look at all the different types and discuss their uses.

In 1985 Sony and Philips developed a standard for writing data to compact optical disks previously developed for the music industry.  The media became widely known as CD-ROM or compact disk read only media as it could be read by an optical drive, but no data could be added.  Since the capacity of these disks were many times the capacity of floppy disks, manufacturers quickly began distributing their software on CD-ROM.  These disks were created by stamping a reflective sheet with a glass master similar to the process used to make vinyl records in the days before audio CDs.

As technology continued to develop, new CD-R or CD Recordable media became available where data could be written to a disk with a CD “burner”.  The new CD-R media had a dye film instead of a reflective film and the CD burner used a laser to alter the reflective properties of the media.  The changes, once made, were permanent making it a good format for permanent backups and small run software distribution.

Later CD-RW or CD ReWritable media and burners were developed allowing usage similar to a floppy disk with much greater capacity.  The rewritable media would allow data to be written, erased, and modified.

In a similar evolution to CDs, DVD media also made the transition to the computing world.  Originally developed as a medium to store and distribute video, the potential for data storage was quickly recognized and a consortium of computer manufacturers agreed on a standard format.  The purpose of this agreement was to help avoid a format war similar to the VHS/Betamax battle of the early 80’s.  Unfortunately after the initial DVD-R standard was created the war was started anyway with the creation of a DVD+R format which is similar to, but incompatible with, the DVD-R format.  This means that you need to make sure your burner is compatible with both formats or choose the correct media.

Like CD’s, DVD’s have a RW version and media is available for both formats; DVD-RW and DVD+RW.  These disks have a storage capacity that is 6.4 times that of a CD.

Another innovation in this technology was the creation of dual layer media.  Introducing a second dye layer to the disk allows almost twice the amount of data to be stored on a single disk.  Dual layer media is available in both write once and rewritable format.  This media is identified by adding DL to the end of the name such as DVD-RW DL or DVD+R DL.

The latest addition to this media family is Blu-Ray.  As the next generation of storage technology was being developed a “media format war” of types began again.  This time the battle was short lived and the proponents of HD-DVD conceded in February 2008 that Blu-Ray would be the new standard.  With single layer disks storing up to 25 Gb of data and dual layer storing 50 Gb, this format is suited for storing high definition video or large quantities of data.  This media is labelled BD-R for recordable media, BD-R DL for dual layer recordable media and BD-RE for erasable media that can be written to over and over.

Here’s a summary:

Media                                                   Data capacity                                     Music/Video capacity (Minutes)*

CD-R, CD-RW                                      700 Mb                                                 80

DVD-R, DVD+R,                                   4.7 Gb                                                   535/60

DVD-RW, DVD+RW

DVD-R DL, DVD+R DL,                         8.5 Gb                                                   970/120

DVD-RW DL, DVD+RW DL

BD-R, BD-RE                                        25 Gb                                                    2850/350

BD-R DL                                               50 Gb                                                    5700/700

*Note that video capacity is approximate and assumes no compression.  Compression increases the video capacity with some sacrifice in picture quality.  HD video uses considerably more space.

One last technology on note is LightScribe.  Using LightScribe media in a compatible burner, a label or design can be etched into the top of the media.  LightScribe enabled burners will be labelled on the front and include software to design the label.

At some point in our lives I think everyone faces this question in one form or another.  In many cases the answer is obvious and in others it is very complex.  With PCs and servers the answer tends more toward the complex end of the scale.  We need to first find the reason for asking the question.  Is the computer performing poorly?  Is it not working at all?  Does a new application call for higher specifications?  Many questions immediately come to mind when faced with a broken or poorly performing computer.   How old is the system?  Has something recently been added that may have caused the problem?  How is the system used?  Is it a home computer used for email or games or is it used to generate income?

Poor performance may not indicate that a system is ready for retirement.  Performance can be affected by a number of factors including malware, fragmentation, or even the number of icons on the desktop.  When you consider that replacing a computer will require reloading of all programs and restoring data, it makes sense to first attempt to do the same to your existing computer.  Most PCs now come with recovery disks that will wipe the system out and restore it to the original factory condition.  You may even find that when you start to reload your programs there are a number that you no longer use.  Restoring the system to factory condition will ensure that files are not fragmented and any malware that may have been present will be eliminated.  This is also a good time to make a copy of your data to store in a safe place.

If restoring the system to its original state does not make enough of a difference then it may be that current operating system and software demands are too high for your hardware.  This can happen because newer software and operating system updates are often more demanding on resources.  At this point you have reduced your system to only the bare necessities and have gathered and tested all of your applications by doing the earlier restoration.  Make a list of your applications to have available when you look at new PCs to make sure there are no compatibility issues.

In some cases a system is too old to even consider restoring to its original state.  If you are running an operating system earlier than Windows XP or Server 2003 then you are due for a replacement.  Systems this old are at risk of hardware failure and most are also very large power consumers.  CRT displays are also more power hungry than their flat panel equivalents, which also provide clearer and brighter images.

How a system is used is another factor to consider.  With malfunctioning hardware on a business PC or server, it would be wise to consult a technician to estimate the cost and time involved to repair a system compared to replacing and restoring it.  The reduced cost of down time combined with potential productivity gains can often outweigh the expense  of repairing a failed system.  Home PCs are usually not as critical although some would argue that point.  A home PC that is used for video games would benefit from newer and faster hardware, where a system that's used mainly for email and web browsing would not see as much.  I should also touch on the cost of data recovery when a hard disk fails.  If you don't have a current backup of your data you can expect to pay anywhere from $900.00 to $3000.00 to have data professionally recovered and even these services are not always successful.  Once again I can't stress enough how important it is to backup your data on a regular basis.

On a final note, some may have noticed that there was no blog posted last week.  Ironically my home computer failed half way through writing my blog (about computer failures) and I lost my current work.  Fortunately I was already preparing to replace my system and had the new one almost configured.  Of course I also had a current backup to restore my data from.

First of all, thank you Marion for suggesting this week’s topic.

In a few days we will begin the year 2010.  Many people around the world start the year with at least one resolution with the hope of improving themselves or their lives in some way.  I’ve made my share of resolutions to exercise more, eat better, and many other well known promises, so this year why not do something a little different.  This year it’s time to take care of our computers and the data that we have stored on them.

Backups: I keep talking about backups because I’ve seen way too many businesses loose data when it could have been avoided.  We need to be 100% sure that our backups are running, that they are backing up the right data, and that they are restorable.  Many backup software applications have the ability to email someone if a backup fails, but that feature is often not set up.  Take the time to configure and test the notification.  Even with proper notifications configured, it’s a good idea to look at the logs at least once a week in case something got missed.  It’s a good idea to review the backup selections on a regular basis as well.  I would suggest a monthly or quarterly review of what is being backed up compared to what you have stored on your PC or server.  Unless you have very strict control about where files are stored, it’s possible that someone has created a new folder structure, possibly for an important new project, that is outside of the structure that is being backed up.  Finally, test your backups to see if they can be restored.  If you are checking backups regularly then you should only need to test the restore function once a year or when there’s a major change to a computer, but that once a year is critical.  There are many possible reasons for restores to fail so the only way to be sure that you’ve accounted for everything is to test it. 

Archiving: The price of storage and backing up data is getting less and less expensive, but why back up the same data over and over again?  If you have old pictures or documents that you don’t need regular access to copy them to DVDs and store copies in a safe deposit box or other safe location. This will not only ensure that you have backups of your data, but may help you avoid buying a bigger hard disk as well.

Defragmenting: Whenever you install a program or save a file on a computer the bits and bytes that make up the program or file are stored on your hard disk.  As files are created and deleted they leave gaps of unused space on the hard disk.  New files try to fill those gaps and may be split up into smaller chunks to fill multiple gaps.  The result of this after a period of time is that the hard disk may have to jump from one location to another to pick up all of the pieces of a file when you request to open it.  To help combat this fragmentation, Microsoft has included a ‘defrag’ program with Windows.  By default you can find the Disk Defragmenter on your Start Button under Programs -> Accessories -> System Tools.  When you run the program it will scan your hard disk and recommend if a defragmentation should be done.

Desktop Cleanup:  If you’re like me, you save anything you are currently working on to your desktop so that you can easily find it.  Unfortunately I seem to have trouble moving or deleting many of the items once I’m done with them so my desktop gets cluttered.  Apart from the obvious effect of making it harder to locate things, a cluttered desktop also impairs performance.  Move those saved documents to a folder in My Documents and delete shortcuts to programs that are also available in your Start Menu.  Yes, that goes for Mac users too.

This year lets all resolve to make our computers healthier.  A little bit of work up front and a few good habits can reduce stress by helping avoid potential problems and increasing performance.  Of course that doesn’t mean that we can give up on our diet and exercise programs.

Basic Business Systems entered the internet backup market about four years ago.  At that time most companies relied on magnetic tape to backup their data and home users either didn’t backup at all or just burned important files to CDs on a regular basis.  Our experience has been that tape backups can be very unreliable for a number of reasons.  Probably the biggest problem with tapes is that someone has to put them in the tape drive every day.  We found that in some cases people didn’t realize they should be doing that or just became complacent and eventually forgot about it.  The other big issue was reliability.  Tapes have a finite life and because they have to move to work they and the tape drives are subject to wear and contamination.  Backups should be checked every day to ensure that they were successful and they really should be tested regularly to verify that the data can actually be restored.  On more than one occasion we were called in to help a company that had a drive fail only to find out that their backups were either very old or non-existent.

Internet backups have helped address most of the challenges we faced, but also presented a few new ones of their own.  The first step to simplifying and increasing the reliability of backups was to remove the human factor for our clients.  Internet backups, or remote backups, store the data on a remote server that is always available eliminating the need to change something such as a tape.  By hosting a number of clients on a single server we were able to build in redundancy that would not have been cost effective for any one client.  This meant that there was clearly a need to encrypt the data to protect it from being accessed by someone other than the owner.  Even transporting the data across the Internet would require encryption to protect it from being read while in transit.  Our approach was to set everything up then allow our clients to set their own password to generate the encryption key.  The encryption key was then used at the source to modify the data to an undecipherable state to be transported and stored on the remote server.  In the event that they needed to restore data, the encrypted files would be copied back to the client’s server and unencrypted using the same key.  Although remote backups are substantially more reliable than tape, they are not infallible.  They do have an advantage over many backup solutions in that they can notify someone if there is a problem.  This could be anything from a corrupt file to an internet connection failure.

For most people, the speed of their Internet connection has increased substantially over the past few years.  Even with the new technologies and lower costs it can still take many days to backup an entire file server to the Internet.  It is not difficult to backup the server to a portable hard disk and ship it to the backup host in many cases, but you would still be faced with getting all of that data back locally in the event of a major failure.  My recommendation would be to keep a copy of the server backup in a safe location which can be restored as needed, then updated with current data from the online backup.  For home users, it may make more sense to keep important files like family photos on CDs or DVDs in a safe deposit box and only backup current data to the Internet.  This makes sure that your backup is as current as possible while keeping the cost more manageable.

Even if you feel that Internet backup is not for you, please check your tapes!