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In this era of the Internet, Intranets, Extranets, wireless this, wireless that—we are becoming a very connected world. In spite of this, there are many land surveyors who do not use networked computers in their operations. While this may seem odd to some, I can assure you that it is true. One of my good friends, who is extremely tech savvy, does not network his computers together. I know of others who, for various reasons, do not network their computers together.
In this article, I would like to offer some compelling reasons why you should network your computers, and offer advice on how to accomplish this task with very little effort and expense. This subject can get quite complex, so I will cover only the most basic concepts and solutions here. This discussion will also be limited to computers with Microsoft operating systems, simply because space is limited. There are probably few surveying firms using non-networked Apple or Linux machines these days, anyway. This article will focus primarily on the actual wiring and hardware setup involved because operating systems differ as to setup, and your operating system most likely has a very informative help section on this topic. (The exception to this is if you are still running MS-DOS as the primary or only operating system on your machines. You can still network, but it will be a little more difficult because the necessary drivers will be difficult to get your hands on. This article will conclude with links to some informative web pages for additional information.)
Let’s continue by defining what a computer network, or more specifically, a Local Area Network (LAN) is. A LAN is simply a group of computers that are interconnected so resources can be shared. You can even create your network without cabling, although wireless networking is much more expensive and has its limitations. The typical computer network consists of more than one computer (with associated peripherals, such as printers and plotters) with special cables connecting everything together. Each computer has a Network Interface Card (NIC) installed, which is what the cables hook up to.
So, why should you go to the trouble and expense of networking your computers together, especially if you only have two or three computers? The benefits are many. Take the two most useful benefits: file and print sharing. These benefits would enable you to no longer have to keep track of which files are on which computers, work on a file from any of the computers on the network and print to any printer or plotter that is connected to the network from any computer on the network. Not to mention, backing up or archiving files is much easier in a networked environment and virus protection is more effective. With multiple employees, you can take advantage of E-mail, either an Internet accessible E-mail system or an E-mail system that only exists within the confines of your own office. This makes it much easier to convey instructions or questions if you are not in the same room as the other employees, or if you are not always there when your employees are. With a network, you can take advantage of certain software applications that allow for group task assignment or scheduling. You can carry it a step further and create your own intranet, although this subject is sufficiently important that it will wait until next month’s article. If you should desire to, you can configure your network so that each machine could have access to the Internet through one shared, dial-up account.
There are several different network topologies available, but since we are dealing with basics here, we will only discuss two: the linear bus and star configurations.
A linear bus is simply one cable that connects all of the computers together, with a terminator at each end of the cable. Traditionally, this has been the least expensive path, but there is no longer a significant cost advantage and there is one big disadvantage to the linear bus: if there is a problem with the cable, your network goes down. Another disadvantage of the linear bus is the physical act of wiring the machines together. If all of your computers are in one room, you can simply leave the cable on the floor and be done; if you need to run the network cable through walls and into different rooms, then it gets much more difficult. There is also a limit as to how far you can run a linear bus cable. If I remember correctly, it’s about 800 feet.
A star network topology adds a piece of hardware to the equation, that being a hub or concentrator. Each computer is wired directly and independently to the hub. This eliminates the disadvantages of the linear bus and generally makes life a lot easier. In the past, hubs have been rather expensive, but today you can get a five node hub for less that $30. You may not even have to pay for a hub, as some hardware devices come with several network ports built in (shared internet access devices for example).
Either of these network topologies will require that you purchase a network interface card for each machine, and in today’s market, that’s about $20 (less if you shop around). Many newer computers have the network card built into the motherboard so you may not have that cost to deal with.
Network cards have improved dramatically over the years. This is due primarily to plug ‘n play technology, which has made it much easier to install new components in your computer. This brings us to an important point worth discussing. If you are using MS-DOS as your primary operating system (I know you are out there!), you could have a problem here. If you are still using DOS because the software you use is only in a DOS version, that’s fine. If you are still using DOS because that’s what came on your computer, and your computer is old enough that DOS was the only operating system available, that’s another matter. If that is the case, you should do one of two things:
1. Finish this article, turn off the computer, throw away the computer, purchase new computer;
2. Stop reading this article, do something else.
Another note of caution: there is a practical minimum amount of RAM necessary on each machine to be able to run a network, and that is 16Mb. You should already have far in excess of that, but be aware of it if you don’t. One surveyor to another, I think that you should have at least 128Mb of RAM on each of your machines. Sixty-four (64) Mb will work, but there is a big performance difference here. And with today’s prices, it is money well spent.
Back to the point: if you have a computer that does not support plug ‘n play devices, then you are in trouble. I doubt that you will be able to find any network cards today that are not plug ‘n play, but if you do, then you will have to configure IRQ and memory settings on each card. This can be tedious if you don’t know how, but it can still be done. Send me an E-mail if you are in this situation and not sure how to deal with it.
Assuming that your computer supports plug ‘n play devices, read the instructions that come with the network interface card and install a card in each of your machines. When you purchase your network cards, be sure to specify what kind of connection you want. If you are doing a linear bus, ask for a “combo” card that will support twisted pair wire (RJ-45 connectors) or coax. I doubt if there are any still made that support only coax cable.
If you decide to go with a linear bus topology, then RadioShack or a similar retailer should be your next stop. You’ll need enough coax cable to go from the first machine to the last and two terminators, one for each end of the cable. Tell the salesperson what you are doing, and they should be able to help you. You will also need two connectors for each machine. Depending on how much cable you buy, expect to spend somewhere around $20. Assembling the coax cable and connections is fairly straightforward once you have the components in front of you.
If you go with the star topology (highly recommended), your cabling needs can be met at Home Depot, or a well-stocked computer store. Look for Category-5 cable. You can get your cable with the ends already attached or you can purchase bulk 8-pair wire, connectors (RJ-45) and a tool to do it yourself. You will also need a hub of some sort to plug everything into.
That’s about it for the hardware. Install the cards in the computers, run the cable and plug everything in. It’s really much easier than it sounds. If you are unsure about how to do any of this, it will not take you very long to search the Internet for advice. You will know if the hardware is working correctly by booting up each computer. Once the “power on self test” begins, the network cards should begin to transmit packets. Your network cards will have one or more LEDs visible from the back of the computer. If everything is functioning correctly, you will see blinking green lights.
Now you should have physical connections between all of the machines, but we must get the computers to talk to each other. This is done through your operating system, using network protocols.
If you are running DOS or Windows 3.x, it will take a little more effort, and so we will save that for last. If you are using Windows 95, NT or a newer operating system, you should be good to go once each computer boots up. You will probably need to have ready the installation CD for your operating system. With most of the newer operating systems, detection of the network card will happen first. At this point, you will be prompted to select a driver from a list or install from a disk. The specific drivers you will need should come with the network card on either CD or floppy.
Once the network card is configured, it is time to select the network clients and protocols you will use. Consult your operating system’s help section to decide what kind of network client you want to use. As for the protocols, I recommend using two (assuming a Microsoft environment): NetBEUI and TCP/IP. TCP/IP will require certain parameters that you will need to know in advance. Again, consult your operating system’s help section. You will need the following information: domain name or workgroup, IP address for each computer (unless you have a DHCP device in your network) and a subnet mask. Plan carefully here, or you will spend a lot of time tinkering. The domain name or workgroup name will be the same on every computer, while each computer will have a unique name that must be assigned.
Since you may desire to set up your network to access the Internet, take a look at a couple of different devices, if only to get an idea of what is available. First, there are several products available from Ramp Networks (http://www.webramp.com). They have several products that will allow you to access the Internet through one ISP account, and most of its products have built-in hubs so that you will not need to purchase a separate device. Their website also has good information on setting up your network. Linksys (http://www.linksys.com) also has good, inexpensive products to accomplish the task. Devices such as these will require that you use certain IP address ranges and subnet mask, hence the reason for mentioning them here. These devices will generally have a built-in DHCP server as well, so you will not have to manually configure a separate, static IP address for each computer. The documentation that accompanies these devices will answer your questions.
If you do not purchase a device such as those mentioned above, you will likely need to configure static IP addresses for each machine. The DHCP servers mentioned above are the alternative; they dynamically assign an IP address to each computer. In the Internet world, everything operates by IP addresses. There is also an IP address range that has been set aside for internal network use. These numbers are of the range 192.168.xxx.xxx. Internet routers ignore these addresses. So, if you do not have a DHCP server, you will want to assign each of your computers one of these addresses. Start with something like: 192.168.1.1 for your first machine; make your second machine 192.168.1.2, etc. Each of your computers will use the same address for the subnet mask. Use 255.255.255.0 unless you have a device that recommends a different setting. If you get the subnet wrong, your computers cannot “see” each other. You may need to configure other settings, depending upon your operating systems and their documentation.
After you have accomplished all of this, you will want to go to each computer and set up file or printer sharing based on your needs. If, for example, you have a computer that is named JOHN, and you wish to have all of your files on this machine under the directory “PROJECTS,” then you would set up the PROJECTS folder (or directory) as sharable. From your other machines, you will map a network drive to \\JOHN\PROJECTS, such as the drive letter “g.” By doing so, the PROJECTS directory on JOHN will be drive g:\ on the other machines. Printer sharing is set up in a similar fashion. Again, refer to your operating system’s help section.
Now, as for networking computers that use MS-DOS as their primary operating system; you will need to set them up as network clients using software from Microsoft. I’m not sure if this software is still available, but the software I have is called Microsoft Network client version 3.0. It will allow you to set up mapped network connections in your autoexec.bat and config.sys files. Once done, you will have a drive letter assigned to each other computer on the network that you configure a connection to. Send me an E-mail if you have difficulty finding these drivers, and I’ll try to help you locate them.
As you can see, small office networking can be a very complex endeavor, but one well worth the effort. I may have left out some important pieces of the puzzle but the following links will help. There is also a great deal of information at your disposal from any of the popular search engines. If you find that any of the information I’ve outlined is contradictory to your experiences, or you need additional information, please send me an E-mail message to: firstname.lastname@example.org.