Eldar said:
Yea, I've had people ask me why not try and go to UNSW or USYD, but I don't see the point. I've been to UoW many times for various things, and I love it. The campus isn't huge and it seems nice. Plus it's so close (for me anyway).
What are you majoring in? You've got quite a few Stat subjects there so I'm inclined to say Statistics.
Also what was Mathematics for Cryptography like? It's hard to get much information on it, and I don't know anyone who has done it.
I'm double majoring: one major in stats, the other in pure and applied. I am working towards getting statistical qualifications and working in that area.
With regards to the mathematics for cryptography, there is a lot of information to digest. In terms of technical challenges, it is not as hard as some of the other high level subjects, but there is a lot to go through.
I'll start with a preamble.
Cryptography as you probably know is about making knowledge secret so that only a person with the right "key" can make the information sensible.
Now the holy grail of cryptography is completely unbreakable asymmetric cryptosystems: that is, public key cryptography systems.
The reason for this is because if you use a standard symmetric system, you need a way for the other person to get the key so they can read it: the thing is you need a secure channel to distribute the key! As you can see this creates problems.
Public key cryptosystems don't have this requirement. You have two keys: an encoding key and a decoding key, and the person can encode with separate information to that of the decoder.
Based on that, the question arises: how can we do that and how can we check whether the method is good?
The answer is currently that using number theory it is "believed" that its hard to crack codes that have been created using number theory techniques. It might be easily breakable (my personal opinion is that it probably will be in the future), but so far no-one has done so, and this only builds confidence that the methods are secure.
Also its important to realize that these methods are "easy to do", but "hard to undo". This is an important property that these methods have because without it, it would be useless.
Based on the above, the whole course teaches number theory and specific applications of that to cryptography: this is the whole course. You will start from basic properties like prime decomposition, proofs about primes, and then move into things like solving different types of congruence equations and build up all these results to prove specific results that are used in cryptography.
If you do it, I would advise you to do at least a year of math before you try it (maybe even two). The notes have plenty of exercises and I suggest you pick a healthy mix of them to do.
One other thing is that there is a tonne of material that is covered, just so you know.
). I started my freshman year at a community college, with "Introduction to Algebra" and eventually graduated with a BS in physics from a well-respected university. 
