Tip:
Highlight text to annotate it
X
So welcome to Unit 8. But first let's talk for a second about the final exam. It is unfortunately
quickly approaching, so the final exam will go out on March 24th. And it will be due on
March 31st. And like the midterm, it will be due at 11:59PM, Hawaiian Time, on March
31st. So please don't get mixed up about this, as long as you turn it in on the 31st whatever
time zone you are in, then you are doing fine. Don't try to skate it to the end, we had a
couple of students who got it off by an hour and unfortunately we cannot accept late exams.
But this unit, unit 8, this is security. So far we lived in this wonderful, idyllic world,
internet of the 1980s, where everyone was your friend and you wanted to communicate
with everyone. But the reality of the network today, of the internet today is completely
different, as I'm sure all of you have encountered at some point whether it's phishing attacks
or spear phishing, or trojan horses or warms or whatever the most recent horrific security
thing is going on in the internet, you've heard about it.
So this is going to show up in a number of ways in the material that we cover in the
videos. The first one is, we're going to look at the ways in which we get attacked. So what
are the means that someone else might use, use the network against us. They might try
and capture portions of our addresses, they might try and capture our packets, they might
to eavesdrop on our packets. This is something that's clearly very timely right now, with
all of the discussions in the press about government eavesdropping and things like this.
So you are going to learn about some of the techniques that are being actively used no
to ways for good purposes and to listen into people's conversations. So we're going to
learn about those different types of attacks and then after we've learned about the attacks
we are going to be learning about how you can defend against them. So, some kinds of
attacks we are not going to go to much into, in particular denial-of-service, because it
turns out that it's a very systemsy thing which really depends on how your system is
built. like how you protect your web server from denial-of-service is very different than
how you defend the DNS root servers. So instead we're going to focus on security in the context
of cryptography, so how can you communicate, in a trusted way, across an untrusted network.
Like how can I send Nick an email and know that nobody else could read the email except
for Nick, and how can I be sure that, or how can Nick be sure that I actually sent
the email. So we'll look at a bunch of cryptographic primitives, we'll look at symmetric-key, or
private-key cryptography and a bunch of ciphers, we'll look at ciphers for confidentiality,
so encrypting traffic as well as message authentication codes for integrity and make sure messages
haven't been tampered. We'll also look at, in addition to private-key systems, we'll
look at public-key systems. So I want Nick to get a private key so we can communicate
securely, how do we do that ? Well there is a way to bootstrap it with public-key cryptography,
where I give Nick a public-key, he can use it, but only I have the private copy of it
that allows us to communicate in a secure way. So you're going to learn some of the
beginnings of the basic cryptographic primitives used today in networks to secure them. And
so that will be Unit 8, and that will be the end of the material for this course and so I encourage
you, you are almost there, stick with it and hopefully this last unit will be a lot of
fun for you. Bye for now