Class Reflection Due September 28

1. I probably spend about an hour and a half on the homework assignments.  I feel like the homework and the reading assignments do prepare me for the homework.  It can still be challenging even with doing the reading and attending class, but usually I can figure it out with some effort.
2. Reading the section ahead of time has really helped my understanding in this class.  When I really read the section, even if I have questions, after attending the subsequent lecture, things make a lot more sense and start to click.
3. I need to stay on top of my homework and not get behind.  I need to make sure I plan adequate time to do my homework and the spend time really studying the reading before attending class.  

4.1-4.4 due September 21st

The simplified des type algorithm is really interesting! It takes the bit system we've been working with, but in a different way. It looks simple enough, but must be secure to have worked for so long. 

I had difficultly understanding the s boxes and how to come up with them. I was confused on how they are used. The process for encrypting and decrypting the sea permutations in section 4.4 look tedious. I don't understand how all he boxes and crossing. Arrows work. 

2.9-2.11 due sept 18

Difficult: 

For the one time pad, I don't understand why the key is so expensive to produce. Can't a computer generate a list of random 0s and 1s without too much effort?  Also, I didn't understand how the BBS random generator operated (though it has a great name!). 

Reflection:

It was interesting to realize that companies often had to choose between security and speed.  I didn't realize that security influenced speed and vice versa when it came to encryption, but it makes sense. 

Section 3.8, 2.5-2.8 Due September 16

It was fun to read the Sherlock Homes story.  It's been said several times that a problem with substitution ciphers  English alphabet aren't very secure and it causes problem with authenticity.  In this story because Sherlock figured out the code and sent a message to the killer.  The killer came back to the scene of the crime when the police were there!  Be careful when sending secret messages!

Difficult:
I'm still struggling to understand what to do with a fraction in front of mod n.  I also don't remember how to calculate the determinate of a 3x3 matrix.  

2.1,2.2,2.4 Due September 11

Difficult: I didn't understand the math on our to decrypt affine ciphers.  I was especially confused about converting fractions into a specific number modn.  I didn't understand how they came up with and used the chart of the letters on the top and side with their frequency in the middle.  But it looks like it would be a convenient tool once understood.

Reflection:
It was neat to see how mods can help us decipher affine ciphers.  It was really neat to see the charts used to solve substitution ciphers more easily.  I will definitely use those next time I solve one of those! 

Codes and Ciphers in LDS History

I really enjoyed the lecture today!  It was so interesting to see how codes and ciphers were used in real life situations.  Sometimes it's hard for me to think of times when codes would be used, but I loved seeing how the church used them.  Something as simple as just encoding the key words or phrases really makes the letter difficult to understand.

On the whole, I understood what she was saying.  I was a little confused initially about the difference between a cipher and a code, but after she explained it, it made more sense.  I used to think they were interchangeable.   I didn't understand what the senator/Apostle was writing about that was so secretive that he needed a code.

It was very interesting! I'm glad we got to hear her speak today! 

3.2, 3.3 Due September 4

Difficult:
I had a hard time remembering mods and how they work.  I'm going to need to review them a little more before the rest of it makes sense like the division and multiplication rules.  Last time I really understood the Euclidean algorithm, but I don't understand the extended version.  I'm not quite sure where they are pulling their starting numbers from.  I'm not sure where to stop and how to start.


Reflection:  I learned about congrunces in my 290 class 5 years ago (freshman year was a long time ago!).  It's neat to take principles that we learned (but unfortunately I'm having a hard time remembering them!) and do more with them. 

1.1,1.2, 3.1 due September 2

Reflection: I had no idea that cryptography was used in so many different aspects of my life when identifying yourself online or when making purchases with your credit card or when using digital signatures.  The Euclidean algorithm is really neat!  i'm excited to use it!

Difficult:  I'm still not understanding how cryptography is used to make the above mentioned things work.  When I think of cryptography I think of the cypher we did in class-- different letters meaning different things.  I also don't understand where knowing what prime numbers are fits into our study of cryptography.  The information I read today feels pretty disjointed. 

Introduction, due on September 2

Wednesday September 2:  Answer the following Introduction questions in a blog entry.

• What is your year in school and major?
• I am a Senior studying Math Education
• Which post-calculus math courses have you taken?  (Use names or BYU course numbers.)
• I have taken Math 290, 313, 314, 334, 341, and 371.  This is my last math class at BYU
• Why are you taking this class?  (Be specific.)
• I am taking this class because it is required for my major.  I chose this class over number theory and graph theory because I heard such great reviews about it.   I also chose it because it sounds interesting! 
• Do you have experience with Maple, Mathematica, SAGE, or another computer algebra system?  Programming experience?  How comfortable are you with using one of these programs to complete homework assignments?
• I really don't have any experience using these programs.  I am a little uncomfortable with them, but I am willing to try. 
• Tell me about the math professor or teacher you have had who was the most and/or least effective.  What did s/he do that worked so well/poorly?
• Teachers that I have loved and learned a lot from in the class seemed to care about each of the students personally and want us to learn.  They are patient with us  They can explain things clearly.  It's frustrating to have professors who assume we already know what they are talking about.  My professors are all very knowledgeable, but some seem to have forgotten what it's like to learn it for the first time.  It's frustrating to have a professor tell the class to just stare at the problem long enough and then you'll figure it out.  
• Write something interesting or unique about yourself.
• I love to travel! I did two study abroads: one in at the Jerusalem Center, and the other one tour through Western Europe for my art history minor. 
• If you are unable to come to my scheduled office hours, what times would work for you?
• Sometimes I work during your office hours, but I could come in right after class on MWF.  I have class until 3:20 during the TA's office hours, so I should be able to go in for the last 40 minutes.