Straight through wiring vs crossover:
If you want to set up the simplest form of LAN, there is nothing wrong to make a peer to peer connection by simply hooking up both machines with a direct RJ-45 cable. Watch out, though, you will need crossover wiring in order to connect input to output of the two cards. The wiring is: Pin 1 to Pin 3 and (of course, Pin 3 to Pin t) and Pin 2 to Pin 6 (and again Pin 6 to Pin 2). In this configuration Pins 1 & 3 are one transmit and receive pair, pins 2 & 6 are the second. The remaining 4 pins have no function assigned but still, leave them straight through wired, otherwise you might run into some ground loops. Cross over cables are used quite often between older hubs as a way to daisy chain hubs together, so most retailers that do any networking should be able to make one up for you. Most companies specializing in cables and electronics supplies, e.g. JDRwill either build you one to your specs or they have some standard lengths in stock. For more than you ever wanted to know about ethernet check http://wwwhost.ots.utexas.edu/ethernet/ethernet-home.html
Cable length:
For fast ethernet, the wire length is specified as 12’ (that is foot), to 330’, if you go below that, the echo will come back too fast and you will not get a viable connection. The cable used in 10Base-T is referred to as unshielded twisted pair (UTP ) and the grades recommended for computer networks are Category 3and 5. Often called just Cat 3 or Cat 5. There is a lot of four pair telephone cable out there in various places that people may be tempted to use. It is not recommended at all. It might work but usually not reliably. Cat 3 works fine for 10Mbs networks while Cat 5 is the spec for 100 Mbs. RJ-45 refers to the connectors. RJ-11 is another type of connector for four pair wiring in the communication industry but it won't fit in a NIC.
UTP will come in stranded or solid core with solid core used for longer runs through ceilings and walls and other places where it won't be exposed to any constant bending stresses, while stranded cable would be used for shorter exposed runs. i.e. patch cables.
On a CYA note, any cables that run through a plenum area, ( the space between a hanging ceiling and the real ceiling.) are required by most fire codes to use what is called a plenum grade cable. Plenum grade cables are coated with a plastic that gives of non-toxic fumes when it is burned. I mention this in case someone takes the information presented here and wants to set up their own little network at the office.
Most NIC's (ethernet cards) have configuration and diagnostic utilities available from their manufacturer. If you buy a retail package you probably got the drivers and setup utilities with the card. If you buy the OEM or bulk versions you get just the card which is usually cheaper. Then you can just download the driver sets from the manufacturers web sites.
Usually whenever you start a diagnostic program it looks for the network card first. If it doesn't find something it recognizes it will tell you so. So I would say that most diagnostic tools are specific to the card. Most of the major manufacturers are easy to find. 3Com, D-Link, Kingston, MaxTech and SMC are just a few. Most of the time you can get pretty lucky with most of the generic cards you can buy at e.g. computer fairs but if I can influence the buying decision I like to go with any of the bigger brand names. Tim, a friend of mine from Canada who helped tremendously putting this page together. has had a lot of good luck with D-Link, Kingston, SMC, while at the same time there was a run of 3Com cards that would work but they were horribly slow to boot in a RPL situation.
I am running Wingate on my fastest machine. That is fine but some people like to play Quake II on their fastest machine. and in order to free up as many as possible resources, they should put the Wingate on the least used machine and mostly just use it as a gateway. For some one with a lot more time and patience you can set up a really nice gateway to the internet with Linux. And you could set up a very reliable machine with an old 486. Check out
http:www.betamag.com/beta/1998/linux1.html. The only caveat is that Linux does have a rather steep learning curve, but for the true technical junkie its a lot of fun. If you have any UNIX admin background it's close but there are fine differences.
In closing if you decide to expand your net there are some nice little workgroup type hubs available these days. D-Link makes a nice little unit they call the Hubby that is a five port hub and it retails around $130.00 Canadian so I imagine with a little looking you could find one for under $100.00 US. For my own situation I am looking for a cheap NE2000 compatible ISA card (no more PCI slots available) to put in the old 75 MHz pentium and use it as gateway machine in the future. 100Mbs sounds nice but unless you are transferring large files back and forth on a very regular basis it is a little bit of overkill.
Protocol used: the easiest protocol (language which both machines speak) to use is NetBEUI, because it autodetects any other client on the LAN. The problem about NetBEUI is that every 60 sec, the program will search the network for other clients which brings the CPU usage up to 100%. If disconnected from the network, it will try to establish any connection by force and thus bring the system to crash.
TCP/IP is a much more advanced protocol, however, on a multiple client network you may have to establish domains or a subnet with IP numbers for each computer linked. Again, for peer to peer connection, this is unnecessary.
Ethernet card configuration: If you run autoconfiguration, the two cards will try to go to the highest possible transfer rate that is supported by both. In many cases, this is way above the limitations set by the cable used. Because the test signals are way more simple than any data that "in real life" are transferred, you will have to manually "tame the wild beasts" and set them to lower values, e.g. 10 mibps (full duplex if possible) but that is just try and error.
Simple tests: most cards have a green LED in the back, which shows whether they are physically connected to the network. This is the first and most important check.
SMC provides a diagnostic tool EZSTART, which I don’t know whether it will work with other cards but there is no reason why not. The file name is ez555.exe and can be downloaded from www.smc.com Other cards have their own utilities that can be downloaded from the respective website.
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My own setup
(at the time of this adventure..)
AMD K6 266
Shuttle HOT 603 Mainboard, BIOS version 7, can be downloaded from Shuttle via ftp.spacewalker.com/603.html
Clockspeed: 75 x 4 = 300 MHz
2 x 32 Mb Hitachi SDRAM, 10 ns (EEPROM) set at 2-1-1-1
Internal Zip drive
32 x Maximum CD-ROM
2.1 G Samsung HD
ATI 3D rage II PC2TV Expression video board
SMC 9332 10-100 ethernet card
E-Tech Bullet RPV 33.6 modem
MaxTech XT 7800 17’’ .28 dot pitch monitor
16 bit FX-3D sound card
W95 OSR2.1
The second machine was a 5 year old case with:
AMD K6-200 at 66x3 MHz =200 MHz
Shuttle HOT569
2x32 Meg Micron 10 ns SDRAM
WD 2250 UDMA HD (2.5 G)
24x NewCom CDROM and Soundcard (Hitachi)
SMC 9332 10-100 ethernet card
Jaton 58P 4MB Videocard
PanaSync C1381 monitor
W95 OSR2.1
My third machine was a 5 year old Pentium 75
Intel Phantom Motherboard
48 MB FP RAM (70 ns)
12 x Panasonic/Matsushita CDROM (CR584)
Soundblaster SL20
Maxtor AV7850 HD (850 MB)
Trident 1 MB Video card
IBM 14" Monitor
all housed in a $27 AT case (250W powersupply)
W95 OSR2.1
The first two machines are networked with a HP IIP Laserjet, in addition there is a Plustek FB IV scanner (great little machine) attached to the first machine.
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