All posts by Mr Stratton

Computing teacher and a PT at Coltness High School.
Computing Higher, Revision

Newspaper Exam Guides

Well the Sunday papers have all had a exam guide or two in them. If you missed them then ask about, you might find an aunt or uncle keeping a copy “just in case”

A few of these have been published online over the past few years, but remember before you go searching the net for them, that the computing exam changed in 2005 (other subjects may have changed as well), so be careful to get the right one. I have one or two copies in school and found this one in Dundee.

1. Computer Systems, Computing Higher

Password Security

I found this image on the net and I would have endorsed it whole heartily in the past but my choice of passwords has changed recently.

(c) zonealarm

One of the reasons for making passwords cryptic was to stop the casual observer keyboard watching your password. Now though we tend to use our own machine so the need to protect against observers has lessened. However recent GPU based password crackers have rendered this method of password creation virtually obsolete, so we need a new way to remember passwords.

We are no longer limited to 8 character passwords (can you guess why the limit was 8?), so we could use a sentence. The chances are though, there will be password dictionary based on song lyrics or movie quotes along any day now and Artificial Intelligence might make a good stab at these in the future. So we need a way of remembering passwords that are strong and hard to brute force. I found this image that conveys this perfectly.

(c) XKCD.com

So the next time Facebook or Glow asks you to create a password, try and think outside the box.

REMEMBER attempting to access someone else’s account is illegal and a breach of the Computer misuse act in the UK. The Internet makes it easy to access computers around the world and some countries have more severe penalties.

3. Multimedia, NAB

Multimedia NAB

Took place today and signaled the end of the course.

Remember there will be an exam on the Tuesday we return from holiday, it will cover the Multimedia unit as well as a question on each of software development and computer systems. The resit for the NAB will be on the Wednesday.

The two weeks when we return will be spent on Past Paper questions.  Please make sure that over the Holidays you attempt all the papers I gave you . This will allow you to create a list of “problem topics” we can then use these in class for revision or to create the FAQ on the blog.

Please keep commenting on the blog over the holidays and feel free to drop me an email via Glow. I will be checking this during the holidays.

WARNING!! I know computing is the last exam for a lot of you, that DOES NOT mean you can leave studying for it till the last minute. Little and often is my motto, if you haven’t started then START.

3. Multimedia, Computing Higher

Happy Birthday MIDI

Hello class of the future, I am writing this in November. I have had a guess at when we will get to MIDI.

MIDI is 30 years old! That’s odd, because when you here me talk about it in class most of you will think it’s a modern standard.

There are lots of website that have MIDI music and the quality of the playback depends on the sound fonts or instruments you have installed on your sound card.

Feel free to try making your own MIDI music, if you don’t have a MIDI keyboard, you can always download one.

Computing Higher, NAB

Multimedia Task

  • Download the picture.
  • Create a multimedia document explaining the different graphic file formats using the converted picture as examples
  • Show the effect colour depth has on file size and picture quality
  • Download the sound
  • Use sound editing software to apply a range of effect to the sound
  • Change the sample rate and sample size of the sound and investigate the effects on file size and sound quality.
  • Report back in the multimedia document.
3. Multimedia, Computing Higher

Multimedia Display Technologies

For these I think I will just let the videos do the talking

3. Multimedia, Computing Higher

Contemporary communications

  • buses
  • wireless standards
    • Bluetooth and WiFi have came a long way since they were introduced and are much available than they were only a few years ago. The adoption of these standards has allowed a new range of connected devices and these have increased the uptake of multimedia.
  • increasing bandwidth
  • USB
    • USB has went from 1.5Mbps to 5Gbps in 12 years. This standard interface is by far the most popular wired connection type on computers. It allows the computer to be attached to large range of peripherals, some useful and some not so much.
  • Firewire
    • or ieee 1394 as it is known on non Apple devices, supports speeds up to 3.2Gbps and is mostly used to connect storage devices. Apple is phasing this out favour of Intel’s new thunderbolt standard.
3. Multimedia

Storage technologies

  • decreasing size and price
    • Processors continue to decrease in price.  We are starting to see an increase in convergence of technologies. Take my first “Smart phone” it is a poor cousin to my current phone. My new phone does everything I can think of it but in 5 years time, I will look back and wonder how I ever did without……?
  • increasing capacity
    • Capacity doubles every 18 months following Moore’s Law. This means that we have seen a dramatic increase in available storage capacity. What will you fill your first Petabyte drive with ?
  • Optical storage
    • CD, DVD & BluRay we are used to these sharing the same physical size but the capacity of each radically different. They accomplish this by using lasers with a much smaller wavelength and more advanced electronics. There is discussion that Bluray will be the last optical storage medium, however, there may be a 6TB successor.
  • Magnetic storage
  • Holographic storage
    • The concept of Holographic storage has been around for quite a while (1960s), we are only now starting to make progress.
    • Holographic storage has a high capacity, fast access times.
    • Stores data in a number of 3D images
    • Hundreds of images may be saved in different layers/full depth of medium
    • Information can be stored in layers (throughout the full depth of the medium)
    • Information can be read a layer at a time (in Parallel) rather than as a sequence of bits