 responsible for the security there, everything from monitoring intrusions to recovering from, you know, if anyone manages to route a box, which, since I've been there, they haven't, but, you know, that may happen, you never know. Anyway, so this talk is really basic, is aimed at those of you with DSL and cable modems. Basically, I can't tell you how many people I hear who basically say, oh, I don't need a modem, I don't have anything important on my computer. And my basic reason, motivation for this talk was to prove that even if you don't think you have anything valuable on your computer, you probably do. In my mind, before I begin, I'll begin in a second, the kinds of information that people don't think of as valuable are financial information. I run Quicken. I have all of my bank accounts on Quicken. If I have a Windows 98 machine that is connected by default, and I'm unfortunately silly enough to share my C drive, people can download my Quicken, and there's Quicken Crack programs, and they can get my password, and they can pay my bills for me, or their own. That's one example. Another example is simply just games. I mean, you've been playing Quake 3 or whatever the new thing is for, you know, 10 or 20 or 30 or 40 or 50 hours, and someone says, haha, I'll delete your Quake file. I mean, there's, thank you for the interruption. Anyways, there are actually valuable pieces of information that you wouldn't think of as valuable. How would you like to have to reformat your pretty new HP? You know how long it takes to install Windows 98 if you've never done it before, and even if you know how? Anyways, I'm going to begin now, because it looks like we're kind of settling down. So, the title of this talk is Home-Based Firewalls and Why You Need Them. Newbie track. There we go. Okay, this is a threat matrix. I'm going to explain it to you. On the top axis are threat OS, the type of technology, cable, DSLR modem, and then I'll just go down really briefly and explain this. Basically, the first threat is the network neighborhood, Microsoft's infinite, let's share our network with the world. Basically, Windows. Technically, Linux can be also classified in here. If you're using something called Samba, Linux can export file systems just like Windows can. And the Samba, unfortunately, in Linux suffers from all of the same security problems in some respects that the Windows one does, unless you set it upright, and it's kind of hard to set up right. Basically, network neighborhood exists as a threat on both cable, DSL, and modem. Now, the main differences between cable, DSL, and modem, modem is generally intermittent unless you've got a least lying, or some people have ISDN, poor people. Anyways, they have ISDN, and it's basically up and down. Cable and DSL are what we call 24-7 connections. They're usually always on, and usually your computer's always connected. So, the threat risk is much higher for cable and DSL as opposed to modem. DOS is denial of service. Everything from the ICMP fragmenting tax that people put out to the ones that took down Yahoo, and simple things like doing WinNuke. If you don't like someone IRC and you winNuke them, that's a denial of service attack. And there's a whole wide class of these, you know, and depending on the OS. All three are vulnerable. All three platforms. Modem, cable, and DSL. IRC, chat attacks. These are probably what I would consider to be for home user who is young. I was saying probably in the 14 to 21 range when IRC is still a cool thing. Basically, that's your group.