CTO Tech Blog

These days we seem to need a PIN or a password for just about everything.  If you follow everyone's recommendations, you'll end up with countless sets of random characters that you are expected to memorize and change on a regular basis.  That seems a little unreasonable for all but the few people who have perfect recall.  While I agree that these rules are important to keep your personal information and finances secure, I think there needs to be a happy medium where the risk matches the required effort.  It's a little risky for me to make suggestions about password security, so please remember that anything short of a completely random mix of characters that only you have memorized is at some level a security risk.

Good security involves three components; something you have, something you know, and something you are.  The something you have may be a bank card, security card, or key fob.  Something you know would be a PIN or password, and something you are is typically a biometric like a fingerprint or retina scan.

PIN numbers (Yes, I do know that the N in PIN stands for number, but it flows better) are used widely in the financial arena to verify that the holder of the card is actually the person authorized to use it.  The weaknesses are that the third component, something you are, is still missing and the other two can be stolen or copied.  Bank cards go missing all the time, but fortunately most do not have the owner's PIN printed on the back.  If a card is stolen by someone who really wants to gain access your best protection is a hard to guess PIN.  Obviously birthdates and anniversaries are not good options as are easy to spot numbers like 5555.  Choose a PIN that is random, then come up with a way to remember it.  For example 4516 could be remembered by the word "deaf" which is made up of the 4th, 5th, 1st and 6th letters of the alphabet.  Patterns on the keypad as you punch the numbers in are sometimes helpful too. One financial institution uses a combination of a couple of passwords for online banking, but only asks for certain characters each time you connect, so the entire password is never typed in a single session.

Email passwords and web site passwords use only one of the three components of good security; something you know.  These passwords are usually at more risk because most information passed over the Internet can be seen by malicious people with basic hacking skills.  Emails are sent in clear text, which means they should never contain passwords, credit card numbers or other important information.  If you're like me, you probably have a number of email addresses and access to many password protected web sites.  My memory is pretty good, but there's no way I could memorize random characters for over 100 accounts and change them on a regular basis.  My solution has been to categorize the email accounts and web sites according to their importance and risk to me.  Some accounts have a unique password, but others are in a category that contains a number of accounts with the same password.  I also use variations of a password in some cases so that I can remember them while maintaining a good level of security.  Newer computers often come with fingerprint readers and password "vaults" where you can store a number of passwords and only access them with a combination of a fingerprint and a password.  Since someone you are is the most secure of the three components of good security, this combination is a good option for keeping your information secure.  I would, however, advise that you keep a list in a safe deposit box as well since hardware can fail or be stolen and you may lose access yourself.

There are many technologies that have been in use for years that are now coming into every day use, as well as improvements on the forefront, such as biometrics in payment cards.  As with any security, the best defence is always knowledge.  If you know what's risky you can avoid it.  With that in mind, I have a few copies of a security reference handbook written by Symantec that I will make available to the first three people who post comments.  Follow up with an email directly to me at gsiverns@basicbusiness.com with your address so I can send you the booklet.

Printed documents are created by attaching ink to paper.  The process involved and the quality of the output varies widely depending on the type of printer used.  Historically there have been many methods of printing and duplicating, but I will only talk about computer printers in this blog.

Printers are classified in one of three categories based on how they produce output.  These categories are character printers, line printers and page printers.  As you might guess the output is transferred to paper one character at a time, one line at a time or one page at a time respectively.  The most popular early printers were dot matrix printers.  These could be either character or line printers.  Dot matrix line printers typically had a row of small wires lined up across the width of the paper with an ink saturated ribbon between.  The ribbon is fed horizontally across the row of wires while the paper is moved vertically.  For each vertical step of the paper a combination of wires would be pushed at the paper causing the ribbon to touch and leave an entire line of dots across the page.  As the paper continues to move up the characters of the output are formed.  These printers are very fast, but are usually limited to text or basic graphics.

Another type of dot matrix printer uses a moving print head with a small number of wires (typically 9 or 24) placed vertically.  The head is moved horizontally across the paper while an ink ribbon is fed horizontally across the head.  As the head moves across the wires are fired in a pattern to create each character of text one at a time.  The head may fire as it travels in one direction or both depending on the printer and the quality of output.  After a line of text has been completed the paper is fed vertically to position for the next line.  Higher quality text could be created using a printwheel or ball printer.  These printers used the same method as many typewriters spinning either a spoked wheel with embossed characters or a gimbled ball with embossed characters.  In the case of a printwheel, a single hammer would fire to push the character on to the paper with the ribbon between leaving the character impression.  Ball printers would lift the entire ball to the paper with the correct character positioned to push the ribbon against the paper.  Neither of these types of printer could usually print graphics, but different fonts were available by changing the wheel or ball.  These are also considered character printers and all of the technologies I’ve mentioned are able to print multi part forms because they use impact to transfer the image.

Newer technologies have replaced most dot matrix printers.  Ink jet printers are character printers that are very similar to dot matrix character printers except that they force ink directly onto the paper through tiny nozzles on a moving head.   The head is moved across the paper while small dots of ink are ejected using either bubbles created by heat or electrically induced constrictions of the nozzles.  As with the dot matrix printers the dots form the characters as the head moves.  Because there is no impact, multi-part forms are not able to be printed.  The small size of the dots used to form the images allow for very high quality text or graphics to be printed.  Most inkjet printers also use multiple print heads moving together to produce full colour output.  Although there are a number of printers that use six or more heads, it is more common to have only four; black, cyan, magenta and yellow.  The cyan, magenta and yellow can be placed on the paper in close groups of dots causing your eye to see the combined colour.  This allows for a full spectrum of colour reproduction.  Although these printers produce very high quality output, they are usually quite slow and expensive to operate due to the high cost of ink.

For better speed and lower cost of operation without too much sacrifice in image quality there are laser printers.  Laser printers are considered page printers because the entire page or text or graphics are produced within the machine, then transferred to the paper.  There are a number of laser technologies currently in use, but the most common uses a statically charged rotating drum.  As the drum rotates a laser beam is fired at the surface.  A spinning mirror directs the laser from side to side on the rotating drum as it is pulsed on and off.  Where the laser hits the surface of the drum the static charge is removed.  Farther along the rotation the surface of the drum is passed by a brush of charged ink particles called toner.  The toner is attracted to the drum surface where there is no charge laying an image.  Paper is then fed between the drum and another charge which attracts to toner to the paper.  The paper is then fed between a hot roller and a pressure roller to fuse the image to the page.  Colour images are made by rotating the drum four times past four different toner brushes, cyan, magenta, yellow and black, before feeding the paper past to receive the image.  Laser printers are usually more expensive to purchase than inkjet printers, but cost less to operate over time.   

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.