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Upgrade 101 - 8 - Home NetworksToronto Star Fast Forward Upgrade series, part 8, Nov 11/99Preparation and Precautions (READ THIS FIRST)Part 8 of our 10-part series on upgrading computers will focus on connecting two or more computers together into a network. The complexity of task varies depending on the method you use, as do the tools. Cost varies, too. These variables come about because there's more than one way to skin a cat - or in this case to connect computers together. The task can be dead simple and not require you to open the system or it can become so complicated that you need a specialist to do the work for you. It all depends on the method of connection you choose, where the computers are in relation to one another, how many we're talking about, what your expectations are of how they're going to work together, the operating system you're using, and the tasks you want each individual computer to do. Oh, and I shouldn't forget, if you're planning to run a mixture of PCs and Macs, it just got a little more complicated. Whole books have been written on networking and there are people who do nothing else except install and troubleshoot them. There's no way I'm going to be able to duplicate their knowledge or reveal all their expertise here. I'll also be the first to admit that networking is not my specialty - although I have been putting together small home networks with my own equipment for several years, so I'm not totally without some experience. However, in the original printed version of this article, I made some boo-boos. To the best of my ability, and with the often gentle chiding (but not always gentle chiding) of several readers, I've corrected the most egregious of those errors in this online version. Instead of attempting to cram a whole carload of technobabble into this article, and in the spirit of keeping things as simple as possible, I'm only going to hit the highlights. There will be some points at which its not possible to give an explanation without the use of some technical terms, but I'll try to keep these understandable, too. Setting up a home network doesn't need to be complicated, but creating a larger local area or wide area network (LAN or WAN) can be very complex indeed. I urge you to consider, particularly if you're dealing with more than five computers, hiring an experienced network consultant. ChoicesIf you're going to connect two or more computers together you have some broad choices to make. You get a choice of network service (client/server, peer-to-peer), a choice of network hardware (Ethernet, TokenRing), a choice of network software protocol (NetBEUI, IPX/SPX, TCP/IP), and a choice of connection method (wired, wireless, somewhere in-between). There are a series of sub-choices, too, within each broad category. - Network Service -Client/Server: If you're a home - or even small business - computer user with two to 10 computers, there may be some circumstances in which having a client/server network might make some sense, but I can't think of one off the top of my head. As you get much past the middle of the range, it's probably time to call in a network consultant to help you out. In a small client/server environment, one computer is designated the server. All software programs to be run on the individual client systems reside on the server. It likely holds the documents the individual users create, too - but the server itself isn't used by you or an employee. The server sits under a desk somewhere (or in a closet), happily munching electricity and (probably) secretly watching old reruns of "Colossus - The Forbin Project." It also has a name, as in, "Hey, Harry, the !@#$@$ server is down again!" In today's PC environment, the server may be running Windows NT, Novell NetWare, or Linux (rare) or FreeBSD (rarer) or in even rarer holdouts, OS/2 (knock, knock, anyone home?). Individual network stations (the clients), may be running Windows 9x, NT, Linux, or whatever. Simple tasks, such as adding a printer, may make you old before you're done. People who understand these things really well are likely to have certification from a community college or institute of technology. Clent/server networks may be wired or wireless, have fairly robust security measures to prevent unauthorized access, and resist corruption from bad software (although no operating system is 100 per cent bullet-proof). They may use Ethernet or Token-Ring hardware (see below), star or ring topologies (see below), and a variety of software protocols (see below) so long as the whole network uses the same hardware standard and software protocol. Peer-to-peer: It's far more common for someone with up to 10 computers to run what is known as a peer-to-peer network. Each computer on a peer network can be a server, client, or both. Assuming you've done the proper thing with the software licenses (e.g., paid the fees), you can run all software from one system, or duplicate it on each computer. Document files can be centrally stored or stored on each computer. You (acting as the system administrator) or each user can grant or refuse access to documents on his or her individual system, right down to the individual folder level and grant (or refuse) access to any peripheral device on any of the systems (including printers, external storage devices such as Zip drives, and, with the proper software drivers and/or operating system support, modems). The basic network software that allows you to set up a PC peer network comes as part of Windows for Workgroups 3.11, Windows 9x, Windows NT, and Linux – but there are third party network programs as well (perhaps the best known is Artisoft's Lantastic). Peer networking is also built into Macs and the Mac Operating System (MacOS). Peer-to-peer networks may be wired or wireless. They may use Ethernet (common) or Token-Ring hardware (rare) and/or AppleTalk for Macs, a slightly different variety of software protocols (so long as both hardware and software are the same throughout the network), and topologies. Comparing the two basic schemes, a client/server network is more expensive and technically more difficult to set up than a peer-to-peer network. However, the client/server network offers better security and allows for tighter administration – as well as permitting client stations to operate with minimal hard drives and other resources. A client/server network is the only real practical choice if you're attempting to manage more than 10 computers (and if this is you, stop reading, get out the Yellow Pages, and start looking under Computers, Networking, Consultants). - Network Hardware -Ethernet and Token-Ring are not brand names; they are "standards" which describe the method the network uses to determine which computer has access at any given time. If there was no method in place to impose some control over the collection of computers on a network, the resulting babble would bring the network to a halt as all of the machines on it attempted to "talk" at the same time. In very broad strokes, a Token-Ring network is like the storytellers' circle that uses a "talking stick." Whomever has the stick has the floor and everyone else shuts up (except for appropriate laughter and applause). In the case of the computer network, an electronic "token" is passed among the participating systems. Whichever computer has the token can conduct network business (such as sending a file to a printer, for example, or starting a local copy of Word). The "token" is passed among the systems at extremely high speed and each computer in the network gets tiny slices of time through which to transact business. Your file to the printer doesn't get out in one piece; it's broken up into teensy slices (packets) that move whenever your computer has the token. Managing all this activity is what the network software does - in conjunction with a hardware circuit board in your computer. Ethernet uses a different approach. It's more like an old party-line telephone system (except that no eavesdropping is allowed). Your system (again at very high speeds) "peeks" out into the network to see if any other computer is using it. If not, it proceeds about its business. If there's something else on the line, your system doesn't try to interrupt. Instead, it waits, for a random time period then it tries again (otherwise each system would "peek" at the same time and none of them would be able to proceed). You don't need to know precisely how this works because as a user you're not conscious of the process. What you do need to know is that the two basic hardware standards aren't compatible. You need to decide which to use on your whole system. It might help you to also know that Ethernet is by far the most common type of network hardware in use today, that Ethernet controllers are manufactured by a very long list of companies, and that they're less expensive to buy as a result. Both cable and xDSL high-speed Internet service use Ethernet controllers (and you can have more than one in the same computer). An Ethernet network may be wired, wireless, or somewhere in between (see Alternatives, below). - Network Software Protocols -Like all other hardware or hardware-related devices, a computer network requires a software driver to interpret what each computer, its operating system, and the applications you run are doing. The interpreter, or "protocol," then converts that information into a common language that the network hardware can understand. To a significant extent, the protocol(s) you use will be determined by the type of network you set up (client/server or peer-to-peer), the hardware standard in use (Ethernet or Token-Ring), and the operating system in use on the various computers along the network. Common protocols for Novell Networks include IPX/SPX and TCP/IP. Microsoft's client/server networking using Windows NT will also use a variation of IPX/SPX and TCP/IP. Windows peer-to-peer networking primarily uses NetBEUI and can use TCP/IP. You may also want to install IPX/SPX (see below under Direct Cable Networking). Specific drivers and variations will depend on the precise network hardware and operating system you're using - and once you've decided on the network service and related hardware, the choice of which protocol to use is pretty much taken out of your hands. However, did you notice that TCP/IP (Transmission Control Protocol/Internet Protocol) was common to all three network types? This is the software protocol used over the Internet, but it has other uses as well - not the least of which is because it is common to all three instances. It's also used in Mac environments. Often, if you can't get computers to talk to each other any other way, TCP/IP can form a common bridge to allow communication to take place. - Connections -Above, I said there were three basic ways to connect computers in a local area network (LAN): by wire, without wires, and somewhere in-between. It's at this point that the process gets a little complicated (and it's also where I made most of the boo-boos in the published version of this piece – sigh). Whether you choose wired or wireless Ethernet or Token-Ring, you're going to have to find some way to get a network controller into your computer. The controller may be a separate circuit board occupying either an Industry Standard Architecture (ISA) or Peripheral Component Interconnect (PCI) expansion slot in your computer. It could also be integrated into the system's motherboard. If you bring a notebook computer into the mix, the network controller could be on a PC card (formerly called a PCMCIA card) or included in a docking station or port replicator attachment. If you choose a wired Ethernet scheme, the controller you get may have either a port for a 10-Base-T (twisted pair) cable with RJ-45 plug (slightly bigger than the RJ-11 plug for your telephone but looks much the same. It's the newest of the schemes) or for a 10-Base-2 coaxial cable with a BNC connector that looks a bit similar to the connector on your TV cable (but neither the connector, nor the cable, are the same – it's the oldest of the schemes). It could also have both (which gives greater flexibility). This part gets a little tricky because while the most common (and older) speed at which networks communicate is 10 Mbps (megabits per second), there's also a newer, 100 Mbps, standard. The result is that you may see 10/100-Base-T or 10/100-Base-2. Really keen network weenies may also refer to 100-Base-T as 100 Base-TX. Coax/BNC is also sometimes referred to as "ThinNet." Just to get your juices really flowing, there's a third type of cable -- and connector -- you may see, called AUI (in terms of history, it came between the 10-Base-2 coax and 10-Base-T twisted pair). Its connector and socket are a 15-pin plug that resembles (but again isn't the same as) the one used for a game/MIDI port. It may have been a good idea at the time, but it has also fallen into disuse (I suspect from the difficulties in making holes large enough to run its cabling, if for no other reason). There is also a 10-Base-F standard that uses fibre optic cable, but we don't want to go there right now. Both 10-Base-2 and 10-Base-T schemes have advantages and disadvantages, but before we can describe them we need to explore a word I've used but haven't defined yet: topology. "Topology" is a word you see when you start reading up on networks and it can confuse you a bit, but in essence what it describes is the basic shape of your network. You may have your computers in a "bus topology" – essentially an open line (nothing at one end and nothing at the other end, with a series of linked computers in between - this is the topology a lot of home systems would use with an Ethernet peer-to-peer setup). You could also have them in a Ring Topology – a closed circle. Last, but not least, you could use a Star Topology with a central hub and the various computers on the network (as well as other networks) connected like the spokes of a wheel (common to both Token-Ring and Ethernet networks in either client/server or peer-to-peer setups). In a two-station network, you don't need a hub. 10-Base-2 (coax/BNC) doesn't use one and you can hook two systems together with a special "cross-over" cable for 10-Base-T (twisted pair/RJ-45). A bus topology using 10-Base-2 appears less expensive to start when there are more than two computers, because there's no hub involved. All you need is an Ethernet network controller in each system with BNC connectors on them, and an appropriate cable between them. There's a "T" connector used on each system and to add another, you simply attach it to the open end of the "T" replacing a terminator that lives there otherwise. (You may have to buy the "T" connector and terminators separately). In my experience, you're likely to run into trouble with this because this particular connection method simply isn't as popular as the 10/100-Base-2 alternative. It's more expensive to put both connectors on a network card; you can have longer cable runs without running into electrical interference using 10/100-Base-T (185 metres instead of 100 metres). It's also far more common to see a network device with the RJ-45 socket only (yes, there are various devices and hubs designed to allow you to run both cabling schemes on the same network, but there is a premium to be paid for doing so). The disadvantage to the 10/100-Base-T system is that you need a hub to bring it all together if you have more than two computers. Hubs don't have to be expensive, but it's not uncommon to pay between $40 and $150 for one, depending on the number of connections provided, whether it includes both RJ-45 and BNC connectors, and so on. - Wired v/s Wireless -Wired networks require you to run wires. I know that sounds silly, but the implication here is that if you have computers in separate rooms, you don't start working without a drill, hole saw, big vacuum cleaner and a very understanding spouse – unless of course you've just built a new home and had the contractor run the network wires in at the same time as the central vac, cable, and phone hookups. Cost of all this? Well, you can get a network card for a desktop computer for $40 or less, a hub starting at the same price, and network cables in pre-cut lengths for very little. Notebook PC cards are a little more expensive. Cost of running the wires varies. Cost of a consultant just keeps going up. I'm not going to do a long-winded explanation of the various wireless schemes because unless you're a notebook user who likes to roam around your home while accessing other systems in other rooms – or there's a reason you can't or don't want to put wires through walls – and you have lots and lots of money, you're unlikely to invest in wireless LAN technology in a home environment. If enough people write in to tell me I'm wrong, I'll revisit the topic later. AlternativesAlternatives to the full network schemes outlined above include Direct Cable Networking between two computers using serial or parallel ports, connecting two or more systems together through their universal serial bus (USB) ports, creating a clone of a single computer, or systems that connect your computer through your home's telephone lines. - Direct Cable Networking -Let's say you want to connect two computers temporarily (such as a desktop and notebook). If you're running Windows 9x or NT on both systems, you don't need a network card or network cabling. All you need is either a "null" modem converter and a standard serial port cable or a specially modified parallel cable. Both come with software such as LapLink, but you should have no problem finding either one at your local computer store for under $25.
If Direct Cable Networking is installed, open the Network applet in Control Panel (Start/Settings). We're here to add a protocol or check to see whether it's there (even if you do not have a network card in your system). For Direct Cable Networking to work, you need to have the Microsoft IPX/SPX protocol installed. Once all this is done, to both computers, you can now hook them together, either using their serial ports (slow) or parallel - printer - ports (quite a bit faster) and transfer files to your heart's content. If you have two desktop computers in the same room and no other use for their external serial ports, this is a quite cost-effective, albeit slow, way to share document files. Note also that you can run quite long cables between serial ports, but that for all practical purposes you're limited to eight feet using parallel. Other computers on an existing network are also visible and accessible to the computer connected by direct cable. - USB networks -This is a relatively new way to network computers, but has the obvious drawback that it only works if both computers have USB ports available. One example here (but you can find competing schemes if you look hard enough): EZ-Link is a product produced by AnchorChips (www.ezlinkusb.com). It consists of a software driver and a special USB cable. Once you install the driver on both systems, then attach the cable (12 feet standard, 20 feet optional), you can transfer files at up to 1.5 MB/sec between them. There's no reason why you can't connect more than one computer together this way (although you'll need the special cable to go from one to another). Each EZ-Link package with software and cable costs US$89.95. Any other networked computers in your system are visible and accessible through a system connected by EZ-Link, so it's another way to transfer files to that notebook you brought home (and a whole lot faster than Direct Cable). - Cloning -
The Applica U2 is a small box, plus an ISA circuit board you have to install in your system, and a software driver. It includes a 15-foot cable (50-footer optional) from the board to the box, which is about the size of a large package of cigarettes. If you plug another monitor, keyboard, and mouse into the box, two people can use the same computer simultaneously. Each can have his or her own desktop scheme and both can share applications, a modem, a printer, and so on. There is a slight performance hit on the original computer and during my tests, printing often caused the remote system and the host system to lock up. Local distributor, Sak Data Products, tells me that there is now a new software driver that should fix the problem, but also notes that Applica is constantly releasing new drivers to handle specific brands of mice, printers, keyboards and other peripherals with which the product has had known troubles. Cost of the Applica U2 is Cdn.$275 (before shipping, taxes, and - if you don't already have them - monitor, keyboard, and mouse). More info from Sak Data Products, 905-670-5071 or through the links above. - AnyPoint -
As of November 1/99, the cost is Cdn$129 for each internal card or Cdn$149 for each external component (so it will cost a minimum of $258 before taxes to hook two computers together, plus another $129 for each additional system). Its speed, compared to standard network schemes is 1 MB/sec instead of 10 MB/sec or 100 MB/sec. Although Intel released a 10 Mbps internal version of the AnyPoint on November 8, and dropped the prices for both the internal 1 Mbps unit and external parallel port version in the US, there is some confusion about how this works in Canada. An Intel Canada spokesperson tells me that the only AnyPoint currently for sale in Canada (almost exclusively through Radio Shack even though Canadian wholesale distributors have access to it) is the parallel version and that there are no current plans to reduce its price. Although the USB version was given to local writers to evaluate, you cannot find it for sale on the street. Furthermore, said the spokesperson, the 10 Mbps internal card would only be available in Canada if there was demand for it. It looks to me as though Intel has seriously screwed up the marketing of this product, at least in this country. Why AnyPoint may be attractive to many homeowners, despite the high price and slow speed, is that it fits in the niche between wired and wireless networking. AnyPoint uses the existing phone wires in your home, which means that you can have a computer in any room that already has a phone jack. It doesn't require a hub or for any wires to run through walls, floors, or ceilings. According to Intel, AnyPoint sends its signals through the phone wires at a frequency that's high enough to avoid interfering with conversations or telecommunications (such as fax or Internet use). InstallingThere's nothing mysterious about installing a network card in your PC. If you've been following this Upgrading series so far, check last week (sound cards and internal modems). The physical part of the installation is the same as it is for any expansion board (see Upgrading 101 – Part 7 for a quick review). Troubleshooting
Questions?Send them to troubleshooter@computerwriter.com or by fax to 416-425-4644. Components for this series are provided by Grey-Tech Computers, Markham, Ontario, www.greytech.com |
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Back to Upgrade 101 Contents
Under
Start/Programs/Accessories/Communication, look for Direct
Cable Networking. It isn't there? Find your Windows CD.
Start the Add/Remove Programs applet in Control Panel. Click
on the Windows setup tab. All components installed in your
system have a checkmark beside them. Shaded items have more
options. Click on Details to see which ones have been
installed. If you want to add a component (such as Direct
Cable Networking), place a checkmark in the box beside the
name. To remove a component, clear the checkmark. Note that
if you clear a checkmark by accident, that component or
group of components will be removed (so don't change
anything you don't intend to either install or delete).
Follow the instructions in the dialogue boxes.
I
wrote about 
Your network is either going to work as soon as you
install the appropriate hardware and software drivers in all
the appropriate systems and restart them, or it won't. The
common causes if it doesn't work are as follows. 
Part
9, Processor Replacements