Geek Certs Blog

Authenticating users is an important operating system function.

When you login to your computer, which begins when you press CTRL+ALT+DEL on the local keyboard, the Winlogon process (winlogon.exe) begins, and the Microsoft Graphical Identification and Authentication (MSGINA) DLL picks up the username and password to compare it against what is stored in the local accounts database (MSGINA picks this up and passes it back to Winlogon, who actually performs the work). This database is part of the registry. If your username/password combination is there, you log in. If not, you get a message asking you to try again.

Part of the logon process is to next find all of your individual settings stored on the computer and load all of this into RAM. These settings include your desktop colors, shortcuts, programs installed, and user rights associated with your logon profile.

The logon process assigns your user account a type of ‘license’ that stays with you throughout your logon session. This license is called a security identification (SID). Every object on your computer has its own SID. A SID is an alphanumeric string of variable length. It might look something like S-1-2-3 or it might be quite a bit longer.

For example, if you try to use the network to print in the college library, your SID is checked against the printer’s list of who can print. This list is an Access Control List, or ACL. If your user account is in the list, which is an Access Control Entry, or ACE, you get to print!

Further, your SID is checked every time you open a file/folder or use any hardware on your own computer. Each one of these objects has its own ACL and quickly determines whether or not you get to open/use the object. The ACL keeps track of the permissions associated with your SID.

Notice the use of two distinct terms in this discussion: user rights and permissions. MCSA candidates need to differentiate between these and understand that permissions apply to objects (examples are files, folders, printers, network shares, the registry, services, and group policy objects) a user (or other object) attempts to view, modify, or create. A Windows Object Manager manages this.

User rights are used to give permissions to user accounts. Yes, user accounts are a type of object, just like files and folders! However, user account objects are quite different from the other objects I’ve mentioned. An analogy might be that user accounts navigate to, open, and modify files but files do not navigate to, open, or modify user accounts.

Finally it is strongly recommended that you apply user rights to groups and not individual user accounts. Groups are special objects into which user accounts may be placed. We will discuss groups in a later discussion.

Linux is not often seen on the desktop. Indeed, out of 100 desktop (or laptop) computers, you would probably find 5 - Linix, 3 - Macintosh, 90 - Windows, and 2 - other operating systems. Most desktop computers run Windows! Keep in mind though that as you move to the world of servers, especially Web servers, this is not true.

However, this will probably change over the next five years since Dell and Novell partnered up last year to offer Linux on desktops. Dell, as you know, sells computers. Novell sells its NetWare server operating system, but is in the midst of killing it. Novell also sells a network email system named GroupWise. I haven’t heard that GroupWise is going away.

Novell and Dell’s partnership has to do with Novell providing a desktop operating system for Dell computers. The desktop operating system will be Linux SuSe. This will decrease the price of a new computer since Linux is less costly than Windows. Plus, Sun Software gives away a product, Star Office, that is similar to Microsoft Office.

With the above in mind, it’s probably a good idea for you to install Linux and play with it. You can download Open SuSe 10.3 for free, but it’s approximately 4 GB in size. You can purchase a copy too if the download is too large.

I recommend doing this in conjunction with Virtual PC 2007, which you can download free from Microsoft. VPC is a program that you install on your computer. To use VPC, you need to create a virtual machine and a virtual hard drive. Then, install your operating system on your virtual hard drive.

The virtual hard drive is just a file that is stored on your computer (like any other file). This file represents a hard drive that is associated with a virtual machine.

After you create a virtual machine and hard drive, you can install an operating system inside of it. Think of what this means! Instead of reformatting your hard drive, all you need to do is create a new virtual hard drive. You install your new operating system on the virtual hard drive. The new operating system’s settings are stored in the virtual machine.

For example, after installing VPC, open it. Then, click New. The New Virtual Machine Wizard starts. Let’s say that we’re going to install Linux in this VM. Click Next to continue. Make sure that the option to Create a virtual machine is selected and click Next.

In the Name and location text box, type RedHat and click Next. In the Operating system list, Other should be selected. Click the arrow to examine the operating systems you can install within VPC. Linux is not listed (imagine that), and this is why we must select Other. Click Next to continue.

Click Adjusting the RAM, set the RAM to 64 MB, and click Next. This is the amount of your computer’s RAM that will be allocated to your virtual machine.

Click A new virtual hard disk (VHD) and click Next. Set your Virtual hard disk size to 2048 MB (which is 2 GB). This will be the size of your virtual hard drive. Notice that your VPC files are stored by default in My Documents. Name your VHD Linux. Click Next. Then, click Finish.

You just created a virtual machine and a virtual hard drive. In the Virtual PC Console, click Linux and then click Start. Your virtual computer ‘boots’ itself. However, it doesn’t get very far because no operating is installed on the hard drive.

You can install an operating system from a CD or ISO image. On the VPC menu, click CD and then select Use physical drive X: from the list, where X: is the drive letter for your CD. Insert a CD with a Linux operating system on it.

Click anywhere on the black screen of your virtual hard drive. Then, press ENTER. The installation process should begin. Follow the steps from the SuSe Web site to install Linux on your VHD.

Next, follow the steps to log into your new Linux install. If you encounter any problems, Google them! Enjoy this experience because you are pioneering the probable future of the desktop operating system environment.

Today we introduce DNS (Domain Name System) and printer setup as it relates to XP Pro.

DNS is an important concept as it relates to networking. You use it all of the time, but might not be aware of how it really works. Let’s say that at home you use DSL and type www.google.com in your browser. Your browser, which does not know what this means, has to figure out which IP address is associated with these words, so it sends a network message to a server that can translate the name into an IP address. A domain name server answers your browser’s request for translation and provides the IP address that is associated with what you typed in your browser.

Check it out: click Start and then Run. Then, in the Open line, type command to enter DOS mode. From there, type ping www.google.com and then press Enter. The first line of response should be something like:

Pinging www.l.google.com [66.102.7.99] with 32 bytes of data

Notice how your computer figured out (or resolved) the IP address associated with the name you typed? This is DNS. Humans understand words and we can remember them. How often would you use Google without DNS?

As for printers, XP offers little improvement (in my view) over that offered in Windows 2000. Just be aware that you can access and install a printer installed on any PC (including servers), assuming you have permissions to do so (recall groups from a previous discussion). Let’s say that we have a server named Server1-2003 and the group Everyone has permission to use the printer that is shared off of this computer. You have a new Windows XP Pro (XPP) computer that needs to connect to this printer. All you need to do is click Start/Run and type:

\\server1-2003

In this case, your screen will now all of the objects (folders, files, printers, etc.) that you have permissions to see and/or access. If you right-click the printer to which you want to connect, a context-menu appears. Select Install and the printer will be installed on your PC. It’s that easy. Of course, you can use the Add Printer wizard, but this is much easier and is what we use in the real world!

In order to pass the Microsoft certification exam associated with XP Pro, you must be comfortable with how to install and configure printers. DNS is more of a server concept (and most of one server exam is associated with DNS - Microsoft exam 70-291), so it’s important to understand how it works because the 291 exam is hard!

The Microsoft exam for XP Pro is 70-270. You can Google this exam number and learn a lot about what it takes to pass it, including its core objectives. All certifying bodies publish objectives for their exams. The objectives tell you what will be on the exam, by subject. Click here for this exam’s objectives link.

Microsoft Virtual PC (MVPC) is officially out of beta with its general release this week. You can learn more and download the free install program from the MVPC home page.

Check out the recommended requirements too, but pay attention to the fact that you can’t be running Windows 9x or XP Home if you want to install VPC.

If you don’t know much about MVPC, you must check it out. After you install VPC you have the ability to install a number of virtual machines (VM) each utilizing its own virtual hard drive (VHD). Each VM uses the resources of the PC under which VPC is installed. Think of a PC - or a number of PCs - inside a PC.

For example, let’s say you have a beefed up desktop PC running Windows XP Pro and that you install MVPC on that machine. Let’s say that you’re studying for your A+ and MCSE exams, meaning that you need to get your hands on Windows 2000 and Server 2003. To do this, first create a new VM inside MVPC. Name it something like “W2K” as you walk through the wizard. Then, create a new VHD so that you can install your Windows 2000 operating system on that VHD. The VHD represents the hard drive that will house the operating system controlled by your VM.

The VHD is a file on your PC and (if you didn’t change the default location) is stored within your My Documents folder.

It’s important to point out that your install of any operating system within MVPC must be have a license key as this is a fully-functional, fully-usable operating system. So, you’ll need your CD/DVD and license key when you launch your Windows 2000 VM.

When you launch (or boot) your Windows 2000 VM, it’s like you’ve just booted to a brand new hard drive. That’s right, your VHD has a setup program and nothing else on it! After you install Windows 2000 on this VHD you’re ready to go.

I’ve left out a lot of information about MVPC such as more depth on using the application, how to network, share folders with your host PC, and more. Check out its help file or feel free to write me if you need some help.

I’m not too excited about upgrading to Vista from Windows XP Pro, even though I bought my laptop about a year ago. So, I’m going to wait and keep my daily use laptop as is!

Think about it. You need 512 MB of RAM just to run it. Every source I review shouts that it would be wise to pony up with 2 GB of RAM for acceptable performance. Holy cow. On top of this, you also need a good video card that supports DirectX  9.

If your video card is using “shared memory” that will hurt since your system RAM and video RAM drink from the same cup. I downloaded Microsoft’s Vista Upgrade Advisor from http://go.microsoft.com/?linkid=6122429.

It ran pretty quick and recommended that I upgrade only to Vista Business (not Ultimate!). It also flagged some of my hardward and software as potential troublemakers, should I choose to upgrade anyway. I’d run this tool before upgrading.

When a new OS is released, my usual plan is to let others work out its kinks over the next couple of months. This way, I avoid the pain and suffering when missed bugs appear - as they most certainly will.

If you’ve upgraded and have any comments about how it went or what you think, I’d love to hear them.