Although twisted-pair copper cables -- particularly CAT5/5e and CAT6 -- are the most common means for distributing wired network access, the advantages and possibilities of fiber-optic cables become increasingly more apparent. They are useful for transporting data much faster and over larger distances. Also, fiber-optic finds uses inside of buildings (e.g., backbone and horizontal cabling). Like CAT6 and higher twisted-pair types, fiber-optic cabling may be installed in some places as a way of "future proofing".

• In your homework hand-in, please answer the following questions. At no point should any answer consist entirely of a direct quote from another source.
  1. From what material (or materials) is the fiber in a fiber-optic cable typically made? Be specific! Generic terms like "glass" or "plastic" are insufficient. (12.5%)
  2. Draw a cross-section of a fiber-optic cable. (You must create this drawing yourself. Do not copy it from another source!) The different layers should be clearly distinguished and marked. Briefly explain each layer. (12.5%)
  3. Why can fiber-optic cabling avoid signal issues like EMF and crosstalk? (7.5%)
  4. Fill in the blanks below with an appropriate exponent of 10. You must do the calculations yourself and show your work! The first one is already done for you. (21%)

     • 1 kilometer   equals 10 ⁴  decimeters
     • 1 attometer   equals 10   hectometers
     • 1 gigameter   equals 10   dekameters
     • 1 megameter   equals 10   micrometers
     • 1 femtometer  equals 10   terameters
     • 1 centimeter  equals 10   yottameters
     • 1 petameter   equals 10   picometers
     • 1 nanometer   equals 10   zeptometers

     Some of these prefixes are not in the chart given in the lecture slides, so you may have to look them up online.
  5. Fill in the table below with the correct values. You must do the calculations yourself and show your work! The only exception to this is that you may use a calculator for dividing the coefficients of numbers expressed in scientific notation. (24%)

                 +================+===============+========================+
                 | Wavelength (λ) | Frequency (f) |        EMR Type        |
                 +================+===============+========================+
                 | 55 pm          | 5.45 EHz      | X-Ray                  |
                 +----------------+---------------+------------------------+
                 | 510 nm         | 588.2 THz     | Visible Light (Green)  |
                 +----------------+---------------+------------------------+
                 |                | 227 EHz       |                        |
                 +----------------+---------------+------------------------+
                 | 275 nm         |               |                        |
                 +----------------+---------------+------------------------+
                 | 0.23 dm        |               |                        |
                 +----------------+---------------+------------------------+
                 |                | 25 kHz        |                        |
                 +----------------+---------------+------------------------+
                 |                |               | Far Infrared           |
                 +----------------+---------------+------------------------+
                 | 18 μm          |               |                        |
                 +----------------+---------------+------------------------+
                 |                | 450 THz       |                        |
                 +----------------+---------------+------------------------+
                 | 400 nm         |               |                        |
                 +----------------+---------------+------------------------+                            
                             

     Notes:

     • The first two rows have been filled out for you, as examples.
     • For the others, you will have to determine the frequency from the wavelength, or vice versa, and indicate what variety of EMR it is.
     • If it is visible light, please indicate what color: Red, Orange, Yellow, Green, Blue, Indigo, or Violet?
     • The measurements given include prefixes (G, n, and so forth). Your answers must be mathematically correct, but you may use either prefixed units or base units with scientific notation. Do not mix prefixes and scientific notation!
     • However, if you like, you may put the answer twice: using just prefixed units and using just scientific notation. If either is correct, then you get credit for your calculation.
     • For the "Far Infrared" row, a range of values could qualify as such. So, choose ONE wavelength/frequency pair that matches and falls within the that range. You may need to do some research to determine what qualifies as "far infrared". Cite your source.
     • If you're including the questions in your homework hand-in, then you need not include this list of notes.
     • If you copy the plain text table above into your homework file, please be sure to display it in a monospace font (such as Courier or Consolas) so that it maintains neat formatting.
  6. If light travels through a substance at the speed of 2.419 * 10⁷ m/s, then what is the refractive index of that substance? You must do the calculations yourself and show your work! (7.5%)
  7. Briefly explain what macrobending and microbending are and how they contribute to attenuation in fiber-optic cabling. Include drawings/diagrams to illustrate each type of bend -- and the behavior of light upon encountering it. You must create these drawings yourself. Do not copy them from other sources! (15%)
  NOTE: You may wish to include the question text along with your answers, as that can help with organization
• Some of the questions may be answerable using solely the textbook and lecture notes, but others may require some independent research.
• Your hand-in should meet the following specifications:
  • Cite your sources:
    • List any sources consulted. (Including sources used for help with math problems.) These are sources that significantly influenced your thinking or helped you to work out your ideas -- even if you did not take any specific ideas or points from them.
      • Any sources consulted must be explicitly oriented to science, technology, and/or engineering.
      • Generic, non-technology-specific encyclopaedias, dictionaries, websites, etc. are not valid sources.
      • User-created content -- such as blogs and discussion board posts -- should be vetted for credibility before being used.
    • Any direct quotes (or close paraphrasals) -- in other words, where you are using a specific idea or point from a source -- should be quoted and cited with endnotes
    • There may be some overlap between works consulted and endnotes.
    • If you do consult the textbook and/or lecture notes, those must be cited, as well.
    • There are various official citation styles -- MLA, APA, Chicago, etc. Choose one that you know. At the very least, your citation should make it easy for me to find your source -- and place within the source, if applicable.
    • For web links: Please include the URL so that I have the option to look up your source, if I wish to.
  • Any drawings/diagrams should be clear and easy to understand. Ways to make a drawing include:
    • In some kind of bitmap editing program, such as Paint.
    • Within your word processor, using the drawing utilities.
    • Drawing on paper and...
        * scanning your drawing to an image or...
        * taking a digital photograph of it.
      You would then import this image into your document. In either case, the image must be neat and easy to interpret.
  • Skip lines -- but not an excessive amount! -- to indicate divisions between questions and answers.
  • 0.5-to-1-inch margins
• For any math problems, you should show your work! This can either be incorporated into your PDF as images OR handed in to me separately, in physical form.
• There is no need to consume several lines at the beginning with information like class, date, etc. Your name will be sufficient.