COMPUTING FOR THE BEWILDERED By Bill Hayles Hello, again. You'll probably be reading this just before Christmas, so may I wish you all a very Merry Christmas and a happy and prosperous New Year. Thank you for all your e-mails and words of encouragement about this column. They're appreciated, even the critical ones. SIMPLE LOCAL AREA NETWORKING Part 1 Many of you will getting new computers for Christmas. For some of you it will be your first, and this column has been catering for you for the last few months and will continue to do so in the New Year with my promised series on The Internet. But for others, it will be a replacement for an old faithful - a machine that has served you well for, perhaps, the last three years, but which is now getting a bit long in the tooth, and unable to run the latest operating systems and software. There is no need to discard the old computer. Why not become a two computer family, using your new pride and joy for playing the latest games while leaving old faithful to don the things it's always done well, such as e-mails and word processing. But, wait a minute, you only have one printer and one internet connection. Is there an easy way of connecting the two so that they can share a printer or a modem? What's more, can you read data from one machine on the other? Yes, you can. Quite easily and with very little expense by setting up a Local Area Network. All versions of Windows from Windows95 onwards contain the necessary software. Networking can become a complex topic, and I'm trying to make it as easy as possible. So perhaps I'd better say that everything that follows is, to the best of my knowledge, the truth. However, it's not the whole truth, and there are going to be occasions when I tell you to do something without saying why. If you find yourself wishing to learn more, there are many sites on the Internet and many books that will help you to become expert networkers; all we're doing here is connecting two computers. We'll spread it over two articles, and take it bit by bit. I'll try to keep it as simple as possible. Hardware. You will need: A network card for each computer (maybe) a router "Patch" leads Software All Windows operating systems from Windows 95 onwards have the necessary software as part of the package, although for Windows 95 it isn't installed by default. Other operating systems, such as Linux, also contain the necessary software. We're assuming the use of Windows95, 98 or ME. For other versions, although the basic principle is the same, the details may vary. With Windows XP there is a "wizard" which will help you through the basic steps. The details A network card is a cheap component which either slots into a spare slot on your motherboard (for desktops) or comes as a PCMCIA card (laptops). Many "off-the-shelf" computers, especially laptops, now come with a network card as part of the package. Most network cards are capable of working at 100Mbs if required, but a few of the cheapest may have a maximum speed of 10Mbs (Megabits per second). If installing your own, then, depending on the type it will either be automatically installed after being detected by the system, or you will need to install a special driver from disk or CD-ROM, following instructions given with the card. A router is a stand alone device into which the cables from the network cards are connected, and which controls which signals go to which machine. It is possible to connect two computers without a router by means of what's called a crossover cable. In this case, you'll simply connect each of the network cards on the two computers to one end of the crossover cable. If you have more than two computers to connect, the router is compulsory A router has a maximum speed, either 10Mbs (known as T-Base 10, cheap) or 100Mbs (known as T-Base100, more expensive). A router will typically accept 4 or 8 computers. An ADSL router has an extra input, from the phone line, for an ADSL connection, and is a somewhat more complex beast. If you have two or more computers, and are thinking of getting ADSL for your Internet connection, it will pay you to ask your ISP for a router. This will obviate the need of a proxy as described later. Unless you're using a crossover, the cables are colloquially known as "patch leads" and more correctly as Cat5 cable with RJ45 connectors. They look like large telephone extension leads, and are available off the shelf in a range of predetermined lengths, or made to order by any decent computer retailer up to a maximum length of 100 metres. If you're using a router, simply connect one patch lead from each network card into the router. Don't forget to plug the router into a power source if needs be (some are self powered). Setting up the connections The procedure described here varies somewhat between Windows versions. I'm describing what to do in Windows 98. For Windows 98. Open "My Computer" - "Control Panel" - "Network". You will be presented with a dialog box. First select "Identification". The local area network must have a "workgroup" name - the same for every computer on the LAN, and each individual computer must have a unique "computer name". Let's call our workgroup "FREEBIE" and this computer "MACHINE1". Our second computer will be "MACHINE2". Enter these in the boxes. The Computer Description can be whatever you like. Check that the Access Control is set to "Share" - much easier than the alternative, and all we need. Now select "Configuration" . What you now see will depend on your own setup, but you should see an entry something like TCP/IP < - (description of your network card) . What we need now is at least a vague idea of what TCP/IP, the protocol (i.e. method by which data is transferred) we will be using, and which is now almost universal. What are TCP/IP and IP addresses ? TCP/IP stands for Transfer Control Protocol / Internet Protocol, and is the commonest mechanism by which data is transferred over networks, including the Internet. An IP address consists of four 8 bit numbers (represented in decimal format by a number between 0 and 255) separated by full stops. In addition to the IP address, our TCP/IP configuration will have a Subnet Mask, which tells the network how to distinguish between IP addresses that are part of the same network and those that belong to other networks. The Internet Assigned Numbers Authority (IANA) has reserved the following three blocks of the IP address space for use on private networks that are not directly connected to the Internet: • 10.0.0.0-10.255.255.255 • 172.16.0.0-172.31.255.255 • 192.168.0.0-192.168.255.255 OK, now we can carry on setting up our system. Select "Properties" and you are presented with what looks like a most daunting multi-tabbed dialog box. However, you only need to make a few entries. The most important is the IP address, which we must specify. Each machine on the LAN must have a unique address, and it's much easier to have these close together in the same (private) series. Being completely conventional, I'm going to use the 192.168.x.x range. I'm going to number machine1 192.168.0.1 (and machine2 192.168.0.2). I'll make the subnet mask 255.255.255.0 to ensure only machines in the 192.168.0.x range are included in the local network. Now we need to set the file and print sharing. Since there are no security worries, on both machines we can select "allow others to share" for both files and printers. As for the rest, we're not using WINS, there's no gateway, and we're not using DNS, so we can set those tabs appropriately, and ignore the rest. We'll need to come to terms with some of those only if, and when, we start using an ADSL router. If we've configured both machines, connected all the cables, and rebooted both machines, each should be shown in the Network Neighborhood of the other. Click on "Entire Network", and the workgroup, FREEBIE, should be found. Click on that, and the two machines, 1 and 2, should be present. At this stage, that's probably all. What we now have to do is to share files and printers. That comes next time. That's all for today. Next time, I'll be looking at sharing printers, files and the Internet. If you wish to contact me, you can do so by e-mail to questions@billnot.com. Although I can't promise to give everybody an individual reply, I do read everything. My main computer related website is http://cftb.net. If you wish to join our computer chat discussion group (mailing list) you can do so by sending an e-mail to computerchat@billnot.com with the single word SUBSCRIBE as the subject. If you have been, thanks for reading this.