Network Installation

There are several different types of common networks listed below:

		Connector	Maximum Length	Speed
		AUI/DIX	500 meters(1640 ft)	10 mbps
10Base2	RG-58, thinnet coax	BNC connector	185 meters(607 ft)	10 mbps
10BaseT	Cat 3, 4, 5, 5e, 6 twisted pair	RJ-45	100 meters(328 ft)	10 mbps
100Base-TX	Cat 5, 5e, 6 twisted pair	RJ-45	100 meters(328 ft)	100 mbps
100Base-FX	Fiber Optic	ST, SC		200 mbps
1000Base-T - Gigabit Ethernet	CAT 5e, 6, Fiber	RJ-45	100 meters(328 ft)	1 gbps
802.11b	Wireless / WiFi		150+ feet	11 mbps
Network Type	Cabling	No cabling. Uses Access Point (AP) for connection	150+ feet	54 mbps
10Base5	RG-8 or RG-11, Thicknet coax	No cabling. Uses direct line of sight connections	Varies	Up to 16 mbps

Network Installation:

To construct a Crossover network, cable can be used to directly connect two computers to each other without the use of a hub or switch. The ends on a crossover cable are different from each other, whereas a normal 'straight through' cable has identical ends. Their uses are shown in the following diagrams.

Typically the ports on a hub are MDIX ports. This allows the machine at the other end to utilize its MDI Port (which is what typically a NIC card uses) without the need for a crossover cable. When I say that the ports on the hub are MDIX ports, what I mean is that one of the functions of the hub is to automatically perform the crossover functions, which are required to properly align the cables with each other. When no hub or switch is used, your cable itself must physically perform these crossover functions.

To expand on this a little, when using a hub or switch, the Transmit wires on the workstation need to be connected to the Receive wires on the hub; likewise, the Receive wires on the hub need to be connected to the Transmit wires on the workstation. But if you remember what we stated earlier - cables which are run from PC to Hub are 'straight through' type cables. This is because the hub is providing the required crossover functions internally for you. Thus, when you connect two machines together without the use of a hub or switch, a crossover cable is required - because both 'ends' are essentially the same - a NIC Card. The crossover function must take place somewhere, and since there is no hub or switch to do it for you, the cable must.

What you need

Cable - Be sure the cable(s) you are using is properly rated for CAT 5. It should state clearly on the jacket of the cable, what it is rated at. One option that you have when selecting your cable is to use a pre-made normal 'straight through' cable, and simply whack off one of the ends, and replace with a new "Crossed Over" end. For the purpose of this article, though, we aren't going to go that route. We are going to make the whole thing from scratch - using bulk CAT 5 cable.

Connectors - Crossover cables are terminated with CAT 5 RJ-45 (RJ stands for alking about what Spot had at his bachelor party, I am talking about a tool to strip the ends off the wires you pervert! There are several specialized tools, which can be used to strip the jackets off of cabling. If you do not have access to one of these tools, cautious use of a razor blade or knife should work just fine - but keep in mind if you go the razor blade / knife route, extra special care must be used as to not damage the wires inside the jacket.

Cutters - You need a pair of cutters that will allow you to cut a group of cables in a straight line. It is very important that all the wires are the same lengths, and without proper cutters, this can be a difficult task.

Doing the deed

You now know what crossover cables are used for. You know why you need one. You also know what you need to make one, so I guess we're ready... First thing you will want to do it cut off the appropriate length of cable that you will need. Be sure that it is plenty long enough. If you screw up, and don't cut it long enough, you will have to start all over, and you will not only waste you time, but cable and the RJ-45 ends as well. If you are pulling this cable through a wall, or ceiling, make sure the pulling is completed first. It is much more difficult to pull a cable with the ends already on it. So you have all the parts, you understand the concepts, and you have your cable, lets get started!

Baby steps...

1) - Start by stripping off about 2 inches of the plastic jacket off the end of the cable. Be very careful at this point, as to not nick or cut into the wires, which are inside. Doing so could alter the characteristics of your cable, or even worse render is useless. Check the wires, one more time for nicks or cuts. If there are any, just whack the whole end off, and start over.

2) - Spread the wires apart, but be sure to hold onto the base of the jacket with your other hand. You do not want the wires to become untwisted down inside the jacket. Category 5 cable must only have 1/2 of an inch of 'untwisted' wire at the end; otherwise it will be 'out of spec'. At this point, you obviously have ALOT more than 1/2 of an inch of un-twisted wire, but don't worry - well take care of that soon enough.

3) - Up to this point, things have been pretty easy. Things will get a little bit tricky here, but don't worry, we'll get through this together. We are at a point in this article where a decision needs to be made. You need to decide which end of the cable you are making at this point in time. If you are making your cable from scratch like I am doing while writing this article, you have 2 end jacks, which must be installed on your cable. If you are using a pre-made cable, with one of the ends whacked off, you only have one end to install - the crossed over end. Below are two diagrams, which show how you need to arrange the cables for each type of cable end. Decide at this point which end you are making and examine the associated picture below.