Subtitles of the Movie

A program that you should be familiar with is called VNC or Virtual Network Computing. Now, there's several different versions of VNC out there including Type VNC, which is a very popular implementation and the VNC that just comes installed by default on several Linux distributions and there's probably many other clients out there as well and servers that you can use for VNC. Now, what it is is a cross-platform remote administration Remote Desktop tool. It gives you the ability to log into another computer across the network and get the computer's Desktop, Remote Desktop. Now, what we use this for is to administer computers remotely to get those remote administration sessions we talked about earlier and to get Remote Desktops. It comes available for several different platforms including Windows and Linux. With a lot of Linux distributions, it's built in and installed when you install the box. You can choose not to install this if you'd like. With Windows, usually you have to download a particular package called Type VNC for example and you would install this package on Windows and get it to work and configure it and so forth. Windows actually has built in a type of program that's used similarly to VNC called Remote Desktop. It's not very secure but it pretty much does the same thing as VNC accepted only works from Windows to Windows platforms. It's normally not used cross-platform to connect say a Windows box to a Linux box for example. Now, how you would use VNC is on Windows you might have to install this program. Again, I use the example of Type VNC, which is very popular. You'd have to install it, configure its parameters, configure the server portion if you want to connect to the Windows computer and configure the client portion if you're going to connect to a different computer. Then you would actually just simply connect to that computer. Now I'm going to show you an example of VNC that's built into Linux. As a matter of fact, it's built into our openSUSE distribution and we're going to connect to a one Linux computer to another using VNC. We're an openSUSE computer now and before I use remote VNC, I want to kind of give you an idea of how this works. And we can actually look at the setup of it and depending upon which Linux distribution you use, your screen shot may vary. It may look a little bit different than this. But you can allow remote administration or not allow it. You configure this on the server you're trying to connect to. You may also want to open up a port in the firewall if you have the firewall running. And it would save those configuration settings. Now, we've already configured this on the other computer we're going to connect to so let's look at the viewer itself. This is the Remote Desktop viewer which uses VNC and really it's very simple to use. You can connect to the computer and you would simply put in your options here; the IP address if you want and the default port for VNC is 5900 but it also uses other ports as well in that same series; 5901, 5902 depending up on the Desktop you connect to and we can connect to the computer and we're about to get a login. Or we can actually just pass through login as actually, if you're logged in with an account that has the same user name and password as on the other system, then we'll pass those credentials on. Now, one thing about VNC is that it uses very weak encryption for the most part. It, the authentication is passed in a very weak encrypted form across the network and in some cases it does not encrypt data at all. Now, this can vary based upon the VNC client you use, whether it's Type VNC or a different VNC client or even Remote Desktop on Windows, which kind of uses the same technology. The encryption level is very weak. You actually don't want to use this in a non-secure environment across a non-secure network. If you're on a closed network and you have other security layers built in, you might want to use this just to remotely administer a computer. And the reason we present it here, even though it's not a very secure way of administering a computer is that as a security person, you need to be familiar with it and what its weaknesses are and how it works because you may actually wind up using it. A much better way to use VNC actually is called port forwarding and you can actually port forward or tunnel the VNC protocol through secure shell itself. There's a way to actually go into secure shell and forward all these VNC connections that are happening on port 5900, 5901 and so forth. You can forward those to listen to; to go through ssh and ssh will listen for those connections and forward those to a different port. So it's actually sending the VNC, the unencrypted VNC session through a secure shell encrypted tunnel. Now, in a moment, in the next session we'll actually show you an alternative to VNC that might actually work out a little bit better than uses secure shell natively and that's called the NX client. There are other clients out there that will use secure shell as well. So this is VNC. This is kind of how it works and how it's used and your client may look a little bit different on your Desktop depending upon which Linux distribution you're using or whether you're using a Windows version of VNC.