Geek Certs Blog

Most of us are already are familiar with routers due to DSL, cable, wireless, and satellite Internet services. What’s probably missing is the meaty part of what routers do and how they function.

The basic purpose of a router is to find the best path to a destination. For example, your switch sends a frame to a router via its Ethernet interface. When the router receives the frame, it captures the frame’s destination IP (Internet Protocol) address. Next, the router checks its routing table to determine whether it knows how to get to that destination.

First, the router checks for what is known as a static route. If there is no static route to the destination, next, the router looks for a route discovered via a routing protocol (such as CDP, RIP, EIGRP, or OSPF). If no discovered route exists, the router looks for a default route. Finally, the router routes the (newly created) packet if one of these routes exists (in the order presented). A key point to keep in mind is that if the router cannot find a route to the destination IP address, it will simply drop (or destroy) the frame.

To view the routing table of a Cisco router, type the commands listed below:

show ip route

at the CLI (command line interface) when you’re logged into user mode (immediately after you type “enable”). Before you configure a static route, you should first configure the router’s interfaces.  To configure a router’s serial 0/0 interface with an IP address of 192.168.10.2 /24 and then verify the configuration, type the following commands:

enable

configure terminal

interface serial0/0

ip address 192.168.10.1 255.255.255.0

no shutdown

exit

exit

show ip interface serial0/0

Notice that in the configuration above, I did not specify a data speed rate for this interface, which is what you’d generally expect. If you guessed that I’m referring to the DCE (data circuit-terminating equipment) or DTE (data terminating equipment) status of a router, you’re right! Typically, your router will act as the DTE since the DCE role is usually played by your ISP’s router. If you have a difficult time remembering this, just commit to memory that the “C” in DCE refers to the clock (or timing) and that your ISP will set the clock rate for communication it controls.

At this point, you’re probably wondering just what a static route is. A static route is best used when you want to ‘rig’ how a packet is routed. For example, if your router possesses a discovered (or dynamic) route to a destination IP address, but you always want the router to use another route, you should configure the router with a static route.

You can use static routes for stub routers too. A stub router is a one that is connected to one and only one router. In other words, the stub router only has one path through which to route packets. When this is the case, configuring a routing protocol such as EIGRP is not useful. It’s easier and more efficient to use a static route.

You enter static routes when in global configuration mode (after you’ve typed in “configure terminal” at the CLI). The highly abbreviated command syntax for a static route is:

ip route major_network_address subnet_mask exit_interface

Now, let’s break this down into pieces:

1. “ip route” is the command used to initiate a static route command.

2. “major_network_address” represents the destination subnet for which you are configuring the static route. For example, if you want the static route to apply to all destination hosts in the 192.168.10.0 /24 subnet, then you would list that address in the command.

3. “subnet_mask” is the subnet that this command applies to. So, using the example in #2 above, you should type out the /24 as 255.255.255.0.

4. “exit_interface” is the interface name on your router through which the packet should exit. If you want the packet to exit via serial 0/0, then you would list that here.

The complete command, using the information froma above, would look like:

ip route 192.168.10.0 255.255.255.0 serial0/0

Cisco’s training material tells you that rather than listing your exit interface name, you can also list the IP address of the router on the other end of your router’s interface. However, I don’t recommend this because this slightly decreases your router’s speed.

When I outlined the router’s routing logic, I listed CDP as one of the router’s routing protocols, which is mostly true! CDP helps routers learn about routes, but not very many.

The Cisco Discovery Protocol runs only on Cisco routers and adds to the routing table information about interfaces (and their networks) that are directly-connected to the router. I can’t stress enough that if your router is running CDP and no other routing protocol, your router will only know about directly-connected routes (not routes directly-connected to other routers). One good thing about CDP is that it can learn about switches (Layer 2) and routers (Layer 3). Finally CDP is enabled by default on all Cisco routers. If all of your routers are not made by Cisco, you can turn it off for the router or per interface.

I also mentioned default routes. A default route is known as the router’s gateway of last resort because if no other route exists to a destination, the router will use a default route rather than drop a packet. Most routers should have a default route configured.

A default route is configured similarly to a static route except that the major_network_address and subnet_mask entries consist of all zeroes. If you want packets routed out of your serial 1/0 interface instead of dropping them, then in global configuration mode, type the following at the CLI:

ip route 0.0.0.0 0.0.0.0 serial1/0

Many writers refer to this as the ‘quad-zero’ command. The zeros are what make the route a default route.

Lastly, it’s important to point out that routers make routing decisions based on what they know - not on what other routers know. In other words, if a route is in your routing table, but not in mine, that does not help me at all. In addition, just because a router1 knows how to get to router2, this does not mean that router2 knows how to get to router1.

This means that once you configure your router, you should use the ping command to prove that you can get from router1 to router2 (and vice-versa if you need that type of connectivity).

We’ve covered a lot of material in this lesson. If you have any questions, please feel free to write for clarification.

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.

Most of you are probably quite familiar with a home network where you have one or more computers connected to a DSL or Cable Modem router which is in turn connected to the Internet. If we view your router as another computer (which it is), then you have a local area network, or LAN, and you are its network administrator! As we move through this discussion, remember that we are covering only the basics. Networking is a very complex topic and it takes years of experience and training to develop a complete understanding of how things actually work.

Your computer probably has a network interface card (NIC) with a cable connected to it, a wireless adapter with no cable required, or a modem that has a phone line connected to it. You might even have all three of them in one computer and use whichever one fits your current need. For example, you might use your modem for a dialup connection when at home but use a NIC wired connection at your place of work.

Computers are able to talk to each other through the use of protocols. Think of a protocol as the way ambassadors from different countries communicate with each other: lots of rules and etiquette. Internet protocols work the same way in that there are a lot of rules that tell computers how to speak to one another, how to understand what the other computer said, and when to say good-bye (and how). Sometimes, computers can talk to each other using names, other times they can talk using numbers, called Internet Protocol addresses, or IP addresses. Your IP address is made up of two parts, the IP address and subnet mask. These two numbers combine together so that your computer can be uniquely identified on your network.

Your computer has its own name. All computers do! You can discover your computer’s name by clicking Start, and then click Run. Type command on the Open line and at the DOS prompt, type hostname. The text that appears is your computer’s name! As you probably guessed, many computers can have the same name. So, sometimes, network communication using names just will not work! The larger the network, the more likely that using names will create communication traffic jams! Think of how horrible this would be on the Internet.

To fix this, we give computers names and IP addresses. For example, your Internet service provider’s (ISPs) router, located in your home and connected to your computer (by a wire or wireless), gives your computer an IP address every time you turn it on. This is done via a special protocol (dynamic host configuration protocol, or DHCP). The IP address given to each computer in a network is not given to any other computer. The Internet works in the same way. However, this gets much more complex and is beyond the scope of our discussion.

A router is a special type of computer that is always working to figure out the best path to move data from where it is to its destination. The Internet is made up of many routers that work in conjunction to get this done. Your DSL or Cable Modem equipment is a router. Routers can also act as DHCP servers.

A switch, on the other hand, doesn’t route very well. A switch doesn’t use a computer’s name or IP address. It likes to use your network adapter’s machine address code, or MAC address. Every NIC has its own MAC address burned into it. You can see your NIC’s MAC address by typing in ipconfig /all at the DOS prompt. The MAC address should be the first item on the list that appears, under Physical address. The address will be made up of numbers and letters (0-9 and A-F), known as the hexadecimal number system. A switch keeps something like a spreadsheet (for Cisco, this would be content addressable memory) showing your MAC address and which port your cable is plugged into. Wireless works similarly!

Some LANs do not have a master computer, or server, dictating which users and computers can use resources managed by the server. These networks are named peer-to-peer networks because each peer (computer) is equal to the others. There is no server (a computer with a network operating system installed, such as Windows Server 2003), meaning that each computer has to create rules for who can use its printers and/or shared folders.

A server has the ability to manage all of the computers in its neighborhood, also known as a domain. Think of a domain as a gated community, where a gatekeeper determines who can enter and use the club house, pool, and other amenities. If a computer or user is not registered within the domain, that computer/user cannot use the domain’s resources (such as a printer).

Let’s say that you work at a local bank that has offices throughout the state. Each branch office would be considered a LAN. However, what if we want computers in each office to speak to one another? All we need to do is join the LANs together and create a WAN (wide area network). This is easy to say and difficult to implement! Just remember that to do this, we need routers and ISPs (like Qwest).

When each office connects to the other, the connection might be made using a backbone. A backbone is made up of routers, switches, fast cabling (usually fiber optic cable), and traffic that goes from LAN to LAN (not traffic that would stay inside any LAN).

A network administrator is responsible for ensuring that the computers can all talk on the LAN and/or WAN. This is a heavy responsibility and requires extensive knowledge in how computers, routers, switches, and networks function. Network administrators can prove their skill by passing industry recognized certification exams. For example, after passing four exams, a person could pick up the MCSA (Microsoft Certified Systems Administrator) designation. An MCSA takes care of the day-to-day networking operations. The four certifications exams are: 1) Windows XP or Vista; 2) Server 2003 basics; 3) Server 2003 advanced topics; and 4) Network security (or another approved course).

The MCSE (Microsoft Certified Systems Engineer) is made up of seven certification exams (generally, the MCSA exams plus three more). The three extras include network security and how to manage a domain by using group policies to enforce domain rules. People with either certification are in high demand in the job market.

Certifications also exist for those who need to demonstrate their router and switch proficiency. Cisco is a leader in router and switch hardware and operating systems, and offers a number of industry recognized certifications including the well-received CCNA (Cisco Certified Network Administrator) designation. A CCNA must pass either a two-exam or one-exam certification exam. As you probably guessed, the one-exam option is a bit tougher to pass. Cisco Academies offer four courses designed to prepare students to sit for the exam(s).

The CCNP (Cisco Certified Network Professional) is a CCNA who passes four additional certification exams. These exams are more in-depth than the CCNA exams and relate more to large network administration.

When you copy something (using Edit/Copy from the menu or a key combination of CTRL+C), what you copy is stored in the computer’s memory (RAM). What you copied is stored with its values and formatting. Let’s say you copy some text that has special formatting applied but that you don’t want this formatting in your new document. In this case, don’t select Edit/Paste from the menu. Instead, select Edit/Paste Special. Then, select Unformatted Text from the list. This action pastes in the text but not its special formatting.

In Windows applications and in Windows operating systems, you can learn a lot by right-clicking an object. For example, in a Word document, you can highlight a word (double-click a word to highlight it), sentence, paragraph, or entire document (CTRL+A highlights the entire document). Once you highlight something, right-click it. This opens a context menu that tells you all of the things you can do to the object (in this case, text) you have highlighted. If you select Font from the list, you can format the font for that particular word.

Finally, If you select File and then click Print Preview, you get an idea as to what your document will look like when it prints. Then, after looking over your document, if you click File and then click Page Setup, you can customize what your document will look like when it prints. For example, let’s say that I want my document to print in Landscape rather than Portrait. I can set this here, preview what it looks like, and print it if I like what I see!

Some companies use Microsoft server operating systems to run their Web sites. We could accomplish this by installing Windows Server 2003 on a powerful computer and then enabling IIS (Internet Information Services) on the server. Turn on IIS by navigating to Add/Remove Programs. Then, click Add/Remove Windows Components (in the left side pane). IIS functionality is located in the Application Server item. Click it and then click Details to open a new window. You’ll see IIS listed and you turn it on by enabling its check box. If you’re a current Linux fan, just think of IIS as Microsoft’s equivalent of Apache, the most widely-used Web server operating system used today.

Web pages can be created using applications that hide their complexity. Start out by creating a new document in Microsoft Word and by formatting it with cool fonts, pictures, and graphs. Then, save the document as a Web page by clicking File and then click Save As. You just created your own Web page and saving it as a Web page gives it an .html file extension instead of the standard Microsoft Word .doc file extension.

Creating a Web page in this way is fine when we want to publish a simple page to our company Intranet or our own personal Web site. As you might have guessed, when Web pages are so easily created, they contain a lot of behind the scenes formatting (also known as overhead) that makes the page load slower than if we had created it manually using HTML (hyper text markup language) code.

If you want a professional looking Web site, you’ve got to hire someone who can program in HTML (and a few other Web languages) or you’ll have to learn how to do it yourself. Most Web pages are written in HTML - one of the programming languages that designers use to create Web pages.

You can see any Web page’s HTML code by right-clicking in any text area (don’t click on a graphic). Then, select View Source from the Context Menu that appears to see that page’s HTML code.

A VPN (virtual private network) allows a host (your computer) to communicate over an untrusted network (the Internet) in a secure environment (the VPN). Consider a tunnel that runs through a mountain. The tunnel is pretty safe, but anyone can use it. However, we want a private road that no one else can use. So, we build another tunnel inside the existing tunnel, taking up one of the lanes on the existing tunnel highway (a tunnel inside of a tunnel). The extra tunnel can be likened to a VPN.

Of course, VPNs are done using math and electricity, not cement and roads. For example, Microsoft provides a free VPN client for all of its Windows operating systems. Your network admin could install it on your computer. Then, that same administrator enables VPN capability on the network she manages so that when you remotely connect to the network, you must use a VPN client to connect to the network.

Cisco, and other vendors, sell VPN clients. Cisco’s is not free. They charge over $5,000 for each VPN client you want to install! Yikes. Many people pay the fee though, because Cisco’s product offers robust security.

You use the VPN client your network admin installed on your system by first clicking its icon to start it. After that, you get on the Internet and connect to your company’s IP address (the IP address you have to use to connect to the network). Next, log in to the network while you are safely tucked inside your VPN connection. No one on the Internet can touch your traffic when you’re working inside a VPN. A hacker might see your traffic, but it can’t be understood.

Try it yourself. Create a new network connection on your computer. Click Network Connections in the Control Panel. On the left side of the screen, click Create a New Connection. Pay attention to the windows and select the options to create a new VPN. Just make up a username, IP address, and server name so that you can step through the process. This sets up the client on your computer.

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.

No matter what type of Internet connection we have at home, it seems that we never have enough! For those of you playing games online, faster is always better. When we have a good connection to the Internet, such as DSL or Cable Modem, we consider this to be good bandwidth. This raises the question as to what Bandwidth is.

Before we define this, let’s set a small scenario. Assume that you have a DSL connection at your home and that you are using Qwest as your Internet Service Provider (or ISP). With this in mind, bandwidth can be defined as the amount of data that can be transmitted from your DSL modem to some router at Qwest in a measured amount of time. Let’s select one second as the time measurement since this is quite common. Let’s also define what data is. When we open our browser and type in the Internet address (strangely known as an URL or Uniform Resource Locator) to Yahoo in the browser’s address line, we are sending data to Yahoo’s server. Data is broken down into little pieces – or bits – of electricity. One piece of data might be broken down into millions of bits. You can also think of a bit as being a very small unit of electricity.

In this case, if we measured the number of bits sent by you and received by Qwest in one second, it would probably be somewhere around 384,000 bits per second. We can shorten this to 384 thousand (kilo) bits per second or 384 Kbps.

Let’s change this up for a moment and say that we have an outstanding DSL connection and that we have something like 24 phone lines grouped together (this actually happens). In this case, we would probably have bandwidth of 1,544,000 bits per second. We can shorten this to read 1.544 million (mega) bits per second or 1.544 Mbps. By the way, when the phone company groups 24 phone lines together, this is known as a T1. Businesses pay a few hundred dollars a month for this amount of bandwidth. It’s about 4 times faster than DSL!

So, now you know what 56 Kbps means. This is the fastest theoretical speed we can get when we use a dialup modem to connect to our ISP. Pretty slow, wouldn’t you say?

When you connect to a modem (which is usually installed inside your computer), you use a phone line because phone lines are used for the entire connection from your computer all the way to your ISP. If you use DSL or cable modem, you use a network cable to connect your computer to the DSL or cable modem (this is the equipment that is provided for you by your ISP). A network cable plugs itself into a network adapter (which is also usually installed inside your computer). A network adapter is also known as a network interface card or NIC.

A network cable is different than a phone line cable. The network cable has eight wires inside whereas a phone cable usually has four wires. We’ll talk more about those wires in another post. At the end of your phone cable you should see a clear, plastic jack. This jack has an official name – RJ11 – which means registered jack, #11. Your network cable jack also has a name – RJ45. The RJ45 jack is larger than the small RJ11 phone jack.

Wireless and wired networking works similarly from our viewpoint. Each provides connectivity and bandwidth so that we can all get on the Internet. The equipment differs, but the goal is the same.

Consider how much money that eBay saves (and is able to pass on to us through lower pricing) by not having the traditional ‘brick and mortar’ storefront, as it is called. The savings are tremendous. Of course, eBay makes money by charging sellers a percentage of their gross sales price.

Think about how different eBay is from Amazon (or other non-auction e-merchants). Amazon has to have some type of storefront. The question is, what type? Their store isn’t what you’re thinking of! Their store is a number of warehouses that keeps inventory in a ready-to-ship state. They keep just enough on-hand to meet demand over a short period of time. They figure out how much they need to stock (for each item) by looking at previous sales and then adding to that their guess – or forecast – of upcoming sales. If they guess correctly, they don’t have to pay excess insurance, storage (which includes heat, electricity, storage space), and interest expense (on the money they probably borrow to purchase inventory). They only pay these expenses on things they sell quickly. This process is known as JIT (just in time) inventory. You would learn about this in cost accounting.

When you purchase online, always use a credit card or PayPal. Never pay cash! If you do, you are on your own if a dispute arises. They have your money and you have a poor product or no product at all, and a complaint. I know what you’re thinking: ‘I’ll report them to the authorities, such as the Better Business Bureau (BBB).’ Well, you would need to hop in line because there are tens of thousands of fellow complainants in front of you. And guess what? The BBB only has a few people handling our complaints. So, unless you have a large, valid complaint, you’re out of luck.

However, if you purchase with a credit card or PayPal, then you have a buddy who will fight for you. And, if the online merchant is non-responsive, evasive, or can’t be found, they will almost always get your money back for you. All you need to usually do is complain within 90 days of the date of purchase. If you complain late, then you might lose your buddy. Check with your credit card company to make sure you know when your deadline is to file a complaint against a merchant.

Another important consideration is that every time you do anything that relates to money or your personal identity, check that the Web site’s URL begins with HTTPS before you enter your login name and password. This should ensure that your communication is encrypted and hidden from other Internet traffic. However, keep in mind that if the computer you use for these transactions is not secure, then using HTTPS doesn’t do you much good.

As a side note, you should consider using a number of logins and passwords, depending on the type of account to which you are logging into. For example, if you purchase from a secure vendor, use a certain login/password set for one or more vendors. If you log in to a site that is not secure, don’t use your secure login/password set on that site. Finally, use another login/password set for your bank and other financial institutions. This way, if one of the merchants is compromised, you will not suffer complete exposure when an identify thief gets one of your login/password sets.