Coaxial Cable: Used primarily for TV, Satellite, and Cable Modems. 3 coaxial wires together can also be adapted to work as component or composite wires. In rare cases, Coax can also be used for security cameras or for digital audio. It can also be used move video between rooms: to share a TiVo or cable/satellite box output on 2 TVs.
There are 2 types of Coaxial Cable: RG-59 & RG-6. Since everything is already moving to digital, you should only use the higher quality RG-6 cable. For longer runs, you may want to consider a Quad-Shield cable over the standard Dual-Shield for less signal loss.

Category 3 Wire: Used as phone wire. Each pair of twisted wires handles 1 phone line. Typical Cat 3 wire contains 2 pairs of wire for 2 phone lines, but the plugs can handle 3 pair for 3 lines. For future proofing (for VOIP - Voice Over Internet Protocol or other technologies), it is best to use Cat5e or better as phone wire and leave the extra conductors unused. Phone wire can be Black, Red, Green, & Yellow, or Orange Stripe, Blue, Blue Stripe, & Orange.

Category 5, 5e, 6, & 7 Wire: Used for Internet networks. Your Cable or DSL modem will output this network wire, with Category 5 being the lowest quality and the proposed Category 7 standard the best. All 4 types basically look the same, but the extra twists and better shielding in the higher categories allows for greater amounts of data to be transmitted. This wire can be used for other data applications such as remote volume control knobs, security cameras, infrared (remote control) distribution...


Alarm/Security Wire: This wire is thicker than your Cat 3 cable. It is used to wire Security Systems: Alarm Panels, Window/Door Sensors, Motion Detectors, Sirens...

Speaker Wire: You need to run speaker wire for in wall/in ceiling speakers. You may also run it in wall so that the wires will not be visible on the floor. Just run the wire from terminals behind your entertainment center to wall plates behind your speakers. It comes in 2 conductor (red & black for + & -) or 4 conductor (red, black, white & green = left+, left-, right+ & right-). 4 conductor wire costs more per foot, but it is cheaper to run 4 conductor wire from the entertainment center to the first speaker and then the second. 16 guage wire is probably adequate for most jobs. An inwall subwoofer might warrant 14 or 12 guage.

Optical: Optical wire is currently used for digital audio, but in the future it may be used for many other applications like Internet and Television. Some phone companies are starting to wire new neighborhoods with fiber to provide television. Some structured (bundled) cables come with one or 2 fiber optic wires.

Composite: Also known as RCA cable, this cable is used for both audio and video. The video quality is the worst available and cannot handle HDTV signals, but it is still a very popular and inexpensive format used as a base input/output format in almost every device. Each composite cable contains a main conductor and a shield. Coax cable with its good shielding is the best bet for long composite cable runs.

BNC: BNC cable is used in many of the same situations as Composite or Component cable. Many times the connector can be converted between BNC and Composite or Component. BNC offers a better quality cable (usually a shielded coax cable) with a quick twist connector that cannot fall out on its own.

S-Video: This is a popular video format that is quickly being replaced with DVI and HDMI. S-Video cable is actually 2 Coaxial cables in one. There are 2 signal cables (Y & C) and 2 grounds. You can use 2 Coaxial cables instead of specific S-Video cable or even Cat5e cable although the signal wont be as good with Cat5e because of the lack of shielding.

Component: This video format is better than S-Video but is less common and is being replaced by DVI and HDMI in newer flat panel televisions. Just like composite cable, coax cables also make the best component cables.

VGA (Video Graphics Array): This is the old computer monitor video format which can be found is some old flat panel televisions. Most flat panel computer monitors have now adopted the DVI-D format, leaving the VGA format for CRT tube monitors.

DVI (Digital Visual Interface): This is the current video format for most flat panel computer monitors and was popular with flat panel televisions before the advent of the HDMI format. DVI comes in 3 formats. In DVI-D (Digital) the wire carries only a digital signal. In DVI-A (Analog) the wire carries only an analog signal. DVI-I (Integrated) cables carry both the digital and analog signals. There are also converters that can convert a DVI digital signal to HDMI or DVI analog to VGA and vice versa.

HDMI (High-Definition Multimedia Interface): This is currently the latest standard for high-end flat panel televisions. It carries both audio and video signals.

DisplayPort: DisplayPort is capable of higher higher resolutions compared to HDMI and it also carries both audio and video signals.

Infrared: If you will use your remote in one room, and have your stereo components in another room, then you need a Infrared (IR) repeater. The sensor needs to be located in the room that you will use the remote. The main unit and repeaters should all be with the stereo components. IR repeater systems are usually sold as all-in-one kits, although some types let you use your own wiring for longer runs.



HDCP (High-bandwidth Digital Content Protection): All video formats DVI and later are compatible with HDCP which is a copy protection scheme to prevent theft of TV/movies. Not all devices support HDCP, and you may have trouble connecting two devices if one supports the protection scheme and one does not. Check with your manufacturer's documentation.

Wire Length: Some of the wire types listed above have very short ranges (just a couple of meters) due to their high bandwidth. Some of these specs can be stretched, especially if you are not running the wire at its max bandwidth. For example, VGA, Composite, and S-Video wires are designed to work for a couple of meters, but I have used 50+ foot cables for each.

Cable, Phone, Network, Security, and Speaker wire all allow for very long runs and you should always run these types of wires to a central junction box, usually in the basement (although you may want to run speakers directly depending on the application). The rest of the wire types have limited ranges and should be run point-to-point.

For example: Maybe for a home theater system you will hide the components in another room right behind the TV or in the basement right under the TV. This is more common if you hang a flat panel TV on the wall, you have in-wall speakers, and you don't want to see the stereo components. In these cases the wires should only be a couple of meters long and shouldn't cause any problems. When possible, you should try to run a conduit between the outlets so that you don't need to run wires ahead of time. This conduit can be a 3" PVC tube that makes it easier to run wires between locations. If the wiring closet is directly behind the TV, then you can run wires from a hole in the wall behind the TV to an outlet behind that wall in another other room. As long as both outlets are between the same studs, it should be easy to run the wires without a conduit. This is better than investing in the next generation of video cable before you need it.

Basic Wiring Plan:

For starters, we like to run 2 Coax Cables and 2 Cat5e or better Network cables to every room. One of the network cables will be used for internet and the other will be used for phone with the option to upgrade in the future. The first coax cable can be used for Television (cable or satellite). The second coax has a variety of uses. There are some examples below and also some on the Wire Conversions page. Since we always want to have the option of moving around the furniture (especially in the kid's bedrooms) I like to have 2 sets of the 2 network/2 coax wall plates in each bedroom, setup in opposite corners. You never know where you will want to place a phone, TV, or computer and it is far easier to run all the wires ahead of time.

Once you know what you want in each room, the next decision is where the other end of those wires should be. In a structured wiring plan, this will be the Wiring Panel. If you have a basement, the wiring panel should be down there in a central location, preferably in a part that you don't plan on finishing later. If you don't have a basement, then you will need to use a laundry room, utility closet, or something similar. Remember that you must be able to get the wires from the street (phone, internet, cable) and your roof (satellite, antenna) to this location. This is easy if you have a basement. If not, you may need to work with your builder in determining where they will run the wires from the street.


  • If your satellite company doesn't provide local channels in your area, then you will need to use an antenna to get the local channels. The satellite receiver takes in 2 coax connections: one from the satellite dish and one from your antenna. When the satellite receiver is powered off you can see the local channels.
  • Some DVR (Digital Video Recorder) / Tivo units can record two shows at once. For a Satellite DVR this requires 2 separate coax connections to the satellite (and a 3rd for local channels).
  • Coax can be used to share a video signal in two rooms. Say you want to split the feed from a cable/satellite receiver or a Tivo so that you can watch it in two rooms without paying for a second receiver. You can split the output from the receiver, send it back down to your junction box and then send it back to one or more other rooms. To do this, you will need one or more splitters. For these cases, you need to determine where the signal is coming from and where it is going to. Each of these rooms will need one extra coaxial wire.
  • Many people are starting to download and watch movies and TV shows on their computer. To watch these in the family room, you either have to burn a DVD, have a computer in the family room, or connect your computer to the TV in the family room. Microsoft, Apple and other companies have products that are either fully capable Media Center computers or specialty products geared toward television. If you don't have one of these, then you can take the output of your computer, run it through a RF Modulator which can convert Composite or S-Video (which cannot be run long distances) into Coaxial cable (which can be run long distance).
  • An RF Modulator can also be used to convert the audio/video output of a DVD player or any other device that outputs a Composite or S-Video signal so that it can be sent to other rooms.

  • Coax cable can be used for surveillance systems. Some video cameras output coax cable. Others output composite cable which can be converted to coax using a RF Modulator. There is also special CCTV (Closed Circuit TV) wire that combines a coaxial cable and 2 additional wires for power.
  • A composite based surveillance security system can be directly connected to a television instead of using a RF Modulator. The disadvantage here is that only one camera can be connected to one television. If you attempt to split the composite wires and run long lengths to multiple televisions, there will be too much signal loss. Most televisions have connectors for only one composite input, so they can only handle one camera.
  • There are now Cat-5 networked cameras that have their own IP Addresses. These tend to cost more, but they can easily be viewed by any computer on the network. Most come with software that will allow you to record using your computer and to view the cameras remotely over the internet. Note: You can technically do this with any type of camera, but you will need special hardware and software to get the video signal into the computer and to then record it or broadcast it on the internet.

  • In-wall/In-ceiling speakers can be used in most rooms. Plan on four to six wall speakers for a home theater system. Other rooms only need 2 speakers. In-wall speakers are best, but ceiling speakers can be used in bathrooms or other rooms where wall speakers are not possible.
  • Even if you do not use in-wall speakers, you will still want to run the speaker wires through the walls to hide them. Determine where the speakers will be and put a wall plate behind that location. Wall plates for floor standing speakers should be at the standard 12" height. Wall plates for speakers mounted to the wall should be directly behind the speaker. Just make sure that your wall plate doesn't interfere with the speaker's mounting bracket.
  • Some speaker distribution systems can support volume controls in each room. These are usually a Cat-5 wire (check manufacturer specs to confirm) that runs from the amplifier to an in-wall volume control. These volume controls look a lot like lighting dimmers. These types of sound distribution systems can be expensive and there are cheaper alternatives. The advantage of these systems is that the control panel will let you can control the volume of all speakers throughout the house, change the input source, skip through songs, or even act as an IR receiver so that you can use your remote controls from any room.
  • A cheaper method of controlling volume in each room is to use an impedance matching volume control. This is a volume knob that is run in-line with the speaker. This means that you run both the left and right speaker wire from the amp to the knob and then from the knob to each speaker. These systems don't let you do anything but control volume, but they are a lot cheaper and can be used with any type of amplifier/receiver.
  • There are also impedance matching volume controls that are meant to be located with the receiver. These are speaker selectors that take in 1 or 2 pair of speaker wires and then split it up into 2, 4, or 8 different sets of speaker outputs. Some speaker selectors simply turn each pair of speakers on & off. Others let you select from 2 different inputs. Others have separate volume knobs for each speaker output. These are the cheapest and easiest solution to implement. You just need to run speaker wires from the speaker selector to each speaker.
  • Speaker wire comes in 2 and 4 conductor wire. Sometimes, using the 4 conductor wire can be cheaper and easier. Instead of running separate wires to each speaker, you run the 4 conductor wire from the amplifier to the first speaker and then to the second speaker. You use less wire, and 4 conductor wire isn't that much more expensive than 2 conductor wire.

  • Most alarm components are wired with 4 conductor alarm wire. The only special cases I know of are some DSC keypads that have a 5th wire that can be used as an extra zone input. Using this 5th wire isn't necessary unless you want the extra input. You should determine what system you will be installing and do some research before installation so that you know what wires will be required.
  • The Control Panel is the heart of the alarm system. It should be located in the same spot as your wiring panel. A typical control panel consists of a single circuit board mounted inside a locked box. The control panel requires a power supply plus a battery backup that should also be locked up in the box. More complicated systems may require secondary circuit boards for extra zone monitoring or additional features.
  • Every alarm system requires at least one keypad. The keypad is where you activate and deactivate and also program the alarm system. Typically, keypads are located at the primary entrance to the home and in the master bedroom for activation at night.
  • Window/Door Sensors are contact sensors that tell you if a door or window has been opened. Some types of sensors require drilling directly into the door. I do not suggest doing this while the home is under construction. It can void the warranty on the door and that wont make the builder happy if you make a mistake.
  • Motion Detectors are the easiest way to secure your home. 3 or 4 motion detectors can protect an entire floor which is a lot easier than installing a contact sensor on every door or window. The problem with cheap motion detectors is that they can be set off by pets. Motion detectors can also be activated by children wandering around in the middle of the night.
  • Glass Break Sensors are another way of securing many windows with one device. A glass sensor will activate any time it hears glass breaking. Sometimes other noises can set off a glass sensor, but they will usually have a sensitivity adjustment to alleviate this.

Garage Door
  • Prewiring a garage door opener isn't something a lot of people think of, but it can hide unsightly wiring. If your builder will be drywalling the garage, you may want to run the wires ahead of time. Your builder will probably not let you run power, but you can run the other wires. Note: Wiring directions and wire types vary by manufacturer. The necessary wiring is usually included with the garage door opener itself, so you may want to purchase the opener before wiring so that you have the instructions and the correct wire.
  • There should be a power outlet right above where you will be mounting the garage door opener.
  • A button to open/close the garage door should be mounted at light switch height next to the entrance to the garage.
  • You may also want an coded keypad opener mounted outside the house. These units are usually battery operated and wireless but you should verify ahead of time.
  • Finally, you will need to mount sensors at the garage door itself. These sensors will open the door if child walks through the opening as the garage door is closing.
  • You may also want to install a sensor that tells you if the garage door is open or closed. These devices (sold independently of the garage door opener) are usually a simple light that tells you if the door is open. They offer peace of mind and can prevent a trip downstairs to check the garage door right before you go to bed.

Remote Computer Control
  • It is possible to operate a computer from a remote location or from multiple locations. With the right hardware a computer can double as a TV, DVD/video, CD/music player... You might want to read email from your kitchen, or play movies and music off of your computer using your TV. A typical system will have video, mouse, and keyboard. You can have more than one mouse and keyboard if you are using USB. Long USB wires aren't recommended, but if you are only using it for a mouse and keyboard then you can get away with it. I have used a 50' USB cable for a keyboard in the past.
  • There are several options for a video monitor. The first decision is to split the video signal (so that you have the same video at the computer and remotely) or to have multiple monitors. Many computers have 2 VGA/DVI outputs or an S-Video output that you can use as a second monitor. If not, you can still get a second video card for a second monitor. A lot depends on what you will be doing with the second monitor. If you are using a small low resolution computer monitor or a TV, then you might want to use the S-Video output. You may even want to convert the S-Video (plus the audio from the computer) into to coaxial cable using an RF Modulator. If you want a high resolution signal at both computer monitors, then you will have to use a long VGA or DVI cable.
  • You may want to forego a mouse and get a touch screen computer monitor instead. You can perform basic operations with a touch screen but you can't do everything that you can do with a mouse.
  • If you are using your computer as a music server, then you may want to send the audio to another room. Most computers output audio as a mini-RCA plug. This can be split (so that you can keep the audio at the computer) and then converted into standard RCA jacks that most stereo equipment will accept. For long runs, I use coaxial cable for audio and then solder on RCA/Composite jacks to the ends.

Home automation
  • A lot of home automation products are remote operated or they use the house's power wiring and do not require any special wiring. Some very advanced systems will have in-wall touch screen control panels to operate speakers, lighting, security, drape control... from a central location. If you are considering any home automation product, research the wiring requirements ahead of time. You should also view the Home Automation page for more information.

Remote Control
  • Infrared repeaters can be used to transmit remote control signals from one room to another. If your stereo components are in a separate room, then you will need an IR repeater to transmit the infrared signals from one room to another. The wiring requirements vary between manufacturers, so research before you run the wire.

Fiber Optics
  • Running fiber optics is not required today, but the next generation of TV / computer networks may require it. Some all-in-one structured wire products include a fiber optic wire.


Home Theater Wiring, Layout and Setup

  There are special considerations for wiring your home theater or main entertainment room. Before starting, you need to determine:
  • the location of the television
  • is the TV wall mounted, part of an entertainment center, over the fireplace...
  • the number of speakers
  • the locations/positions of those speakers
  • are the speakers in-wall, wall mount, book shelf, or floor standing
  • the location of the stereo components and other electronics


   There usually aren't many choices on where to place the television, especially if it is a flat panel that you are hanging it on the wall. If possible, you will want to place it where the sun will not shine directly on it. The center of the TV should be eye level when you are sitting down. If hanging the TV above the fireplace or some other high location, then get an angled wall mount so that you can tilt the TV downward. Also, placing the TV in the corner of the room makes it very difficult to place speakers for surround sound.

   If this is a wall mount installation, then be sure to have a power outlet and audio/video cables behind where the TV will be mounted. For audio/video cables for a new HDTV, I would suggest at least:
  • 2 or 3 HDMI cables for a cable/satellite HDTV signal, a BluRay player, and possibly a game system like an Xbox 360 or a PS3. Some TVs also take a computer VGA or DVI input, although DVI can be converted into HDMI so a separate cable may not be required.
  • 2 S-Video or component cables for legacy devices like a DVD player, VCR, or an older game system
  • Composite and/or digital optical audio cables to go with the S-Video input

   Although it is possible to make HDMI cables from Cat5 or other wire, you will get the best quality if you run a wire directly from the stereo component right to the TV without any breaks in the wire for a wall plate. It won't look as good to have a hole in the wall with a wire coming out of it, but this hole should be hidden by the TV and there will be a lot less signal loss.

   If this is a TV in an entertainment center or on top of a TV stand with all of the stereo components with it, then you don't need to run any of the wires from the components to the TV. You will have to run speaker wires and other wires in-wall. This is covered in the Stereo Components section below.


   Once you have chosen the location for your TV, you will need to place the speakers. Placement is determined first by the number of speakers. Receivers, amplifiers, and surround sound processors usually indicate the number of speakers as 5.1, 6.1, or 7.1. The .1 refers to the single subwoofer channel. Some systems may have 2 subwoofer channels or two center channels, but these are the basic configurations.
Channels Description
5.1 One center, Two fronts, Two side/rear
6.1 One center, Two fronts, Two side, One rear
7.1 One center, Two fronts, Two side, Two rear


For home theater, all speakers should be at ear height when seated. This will not be possible for the center channel, since that is where the TV is placed. Some systems resolve this by using 2 center channels placed on either side of the TV or above and below the TV. This isn't really necessary. You can just place a single center channel above or below the TV.

   Windows, hallways and open rooms may interfere with perfect speaker placement. If perfect placement is not possible, it is best that pairs of speakers be placed consistently. If one side speaker needs to be close to the corner, then place both of them near the corner.

Types/Categories of Home Theater Speakers

  Some additional speaker terms as they apply to home theater.

Bipole/Dipole: A speaker that uses two sets of drivers to generate sound both forward and backward, or side to side, to create a full diffuse sound field. With bipole speakers the two sounds are "in phase." With dipole speakers the two sounds are "out of phase." In a home theater setup bipole speakers are better behind the listener at the back of the room, and dipoles are better when placed at the side of the listener on the sides of the room. Some speakers have switches that allow them to operate in both bipole and dipole modes.

LCR: Stands for Left-Right-Center, these speakers can be used as main, surround, or center speakers. Some believe that all 5+ speakers in a home theater system should not only be matched but should be identical. LCR speakers are designed for this purpose.

Full Range: These speakers cover the full (or almost full) range of audible frequencies (20 - 20,000 Hz). Full range speakers are usually comprised of 3 or more drivers and are often floor standing.

Bookshelf: As the name indicates, these speakers are small enough to fit on a bookshelf, although they usually sit on speaker stands. They are typically not full range and usually contain 2 drivers: a tweeter and a midrange driver.

Soundbar: A short wide speaker intended to be mounted right above or below a flat screen television. Many flat panel TVs have thin speakers that aren't capable of loud volumes. Sometimes adding just a sound bar will overcome this problem.

On-wall: Many speakers are designed to be placed at least a foot away from the wall. Speakers that are close to the wall can have too much bass and will have reflection problems with sounds bouncing off the wall. If you are looking to mount speakers on the wall or very close to the wall, make sure they are specifically designed for it.

In-wall: These are speakers that are placed inside the wall between the studs. Instead of using a speaker cabinet, the area inside the wall is the speaker box. These speakers work for varied "chamber" sizes since ceiling height and the distance between studs can vary.

In-wall Box: In wall speakers that still have a speaker box. The speaker box must fit in a wall between studs, which means 3.5" deep and 14.5" wide. If these speakers are used on an exterior wall, then you lose the insulation in that wall.

In-ceiling: Similar to in-wall speakers, these are mounted in the ceiling. These speakers usually aim directly down and do not make good home theater speakers, but there are in-ceiling speakers where the drivers are angled toward the listener.

Shielded: Speakers that are magnetically shielded so that they will not interfere with your TV. A non-shielded speaker placed next to a CRT TV can permanently damage it.

Center: A speaker specifically designed as the center channel in Home Theater system. These should be placed directly above or below the TV - with 2 centers they can be placed on the sides of the TV. A center channel speaker plays the action visible on the TV which is usually voices.

Front: Speakers designed specifically as the front speakers in a Home Theater system.

Rear: Speakers designed specifically as the rear speakers in a Home Theater system. Sometimes these speakers aren't directed toward the listener and instead fill the rear of the room with sound.

Subwoofer: A special speaker designed to produce the low bass frequencies, typically below 150 Hz or lower. A subwoofer can sometimes make up for the fact that that bookshelf speakers cannot produce the lower bass frequencies. Subwoofers usually have their own built in amplifier and crossover.






This should give you enough basic information to get going. However, don't try this if you're not fairly mechanical, or adept at similar tasks. CAT5 wiring is touchy, and it's easy to make bad connections (or worse, wiring that almost or usually works, but fails under stress such as high data rates). Diagnosing such problems can be hard, even with expensive test equipment.

I don't discuss here how to drill and fish wires through walls, how to mount a box, etc. This is all the same as for any other kind of wiring, and you can learn it from tons of books available in your local book or hardware store, Amazon, etc. But you'll do more of it than for just adding a new electrical outlet, since for network cabling you can't just shortcut to the nearest one. On the other hand, you can use "low voltage" boxes that have no back, which might be a little easier.

Warning: Wiring of any kind is potentially dangerous. Apart from the usual dangers of tools like wire cutters and drills, you could encounter electrical wires, pipes, etc. when drilling through walls, or encounter other potentially dangerous conditions. If you aren't sure you know what you're doing, don't take the risk, just hire a professional (that will also surely be less stressful, because something unexpected always goes wrong!). I'm not responsible if you get hurt.

Also, although I've tried hard to get this all right, it is entirely possible I've made mistakes here, or that your circumstances may require special materials or procedures beyond the simple cases I describe. Again, I can't predict or evaluate that, and it is your responsibility to ensure that any work you do is safe and legal. I am not a professional sysadmin, electrician, network-builder, etc.; I do software, markup language standards, linguistics, and other things involving bits rather than volts. This page is here to be helpful, but you use it at your own risk.


Basic types of wiring

Ethernet networks are what you generally want for connecting machines, printers, etc. in a single building. Older Ethernets ran on coax cables ("10base-2"); newer ones run on phone-like "twisted pairs": "10base-t" can carry 10 Megabits (not Megabytes!) per second, and "100base-t" can carry 100 Mbps. The network wire and wiring have to be much better to support 100base-t; these days use Category 5 ("CAT5") wiring, which is good to 100Mbps. I wouldn't do anything less in a house just now, except perhaps Apple's wireless networking (because it's sooooo easy).

CAT5 wiring will happily work at either 10Mb or 100Mb, with just about any machine; so you can run a slow net now, and upgrade later without rewiring. One snag is that your network must be arranged in a "star". That is, every device must have a separate wire back to a central point, where a device called a "hub" passes data from one wire to another (fortunately, a fine hub is available for under $50). You cannot just bring the wires from multiple devices together and have it work -- unless you have only two devices total, and a special cable (see below).

New phone wiring (say, from the 1990s on), is usually 6-conductor wire rated "CAT3". This can theoretically handle Ethernet up to 10M bits/second. You can try wiring the extra 4 conductors to an Ethernet connector and see, but it's unlikely to work. This is because you still must have a star, and house phone wiring is very unlikely to be set up that way: builders usually make one long run from each room to the next. Typically you'll have to install lots of new wire. You can of course run the wires on the surface, but I avoid it to protect the wire and appearance.

Hiring wiring done will likely cost $150 to $350 per connection ("drop").


What you will need

If you're doing CAT5 wiring, make sure every part you use is at least CAT5 rated. Lots of CAT3 parts look about the same, but won't handle higher data rates.

  • CAT5 wire or better. Much cheaper by the 1000-foot reel

  • CAT5 'RJ45' sockets for the equipment end of your wires

  • CAT5 modular plugs for the hub end of your wires

  • An Ethernet hub to plug all those plugs into

Don't forget Ethernet cards for your devices (most new machines have them off-the-shelf, as Macs have for years), and short Ethernet cables to go from outlets to devices.

For big projects, you may want a CAT5 "patch panel" at the hub end where all your wires come together. I wouldn't bother, since (a) wiring a plug is no harder than wiring a panel; (b) you still need cables to go from the panel to the hub; and (c) it adds extra connections, so lowers reliability. If you do want to do it this way, you'll need a few extra tools and techniques.

One case where a patch panel might be useful is if you want to share a wire for phone and net: you can run the wires between two blocks mounted side by side, and punch down the network pairs to one block, and the phone pairs to the other.

CAT5 wire

Generally you want 4-pair, 24AWG solid-wire cable rated for at least 100 MHz: make sure it says CAT5. If it doesn't say it, it probably isn't. Don't mess with CAT3; you can probably run a 10MB net on it, but you'll just do it all over in a couple years. It doesn't cost much more to get wire rated for 300 MHz instead of 100, which may work for longer into the future.

Cable comes shielded and unshielded; unshielded should be fine for most applications, but if you're running near other wires a lot, or have big magnets around your house, go for shielded.

The outer casing comes in normal (vinyl, PVC, etc) or the much more expensive "plenum" kind (teflon?). A 1000-foot reel of non-plenum (just fine for most residential use) goes for maybe $80 US.

Alternatively, you could measure and buy each cable individually with plugs already attached. This costs much more and saves little or no work; but for very simple installations you could just staple such cables along moldings, plug in, and be done with it. For a few devices all in the same room this is just fine.

CAT5 sockets

You can get sockets in a variety of forms (much like phone sockets), even at Radio Shack and Home Depot. Surface-mount blocks cost about $6. If you're using in-wall boxes, you can get CAT5 sockets on whole wall plates for maybe $4. But I prefer the modular or "keystone" plates and inserts: you can use them for CAT5, phone, video, audio, etc. at the same time.

Modular plates are about $1.50 and you can get them with 1, 2, 3, 4, or 6 holes (also double-width plates with 12 holes). A wide variety of inserts are available: CAT5 inserts are about $4.50; phone ones $3.75, and so on. Get plates with more holes than you need now, and buy a lot of extra blank inserts ($0.20 or so). You'll need the blanks to fill extra holes until you need them; but just as important, you can drill holes in the blanks and mount other connecters in there. For example, behind my stereo I have a plate with phone, video, and speaker connecters; I made the speaker ones by screwing off-the-shelf binding posts into blank inserts.

CAT5 modular plugs

These look just like phone plugs, only wider. "AMP" brand ones need different crimping tools; make sure you get the right tool for whatever plugs you get. Some manufacturers also make slightly different plugs for solid vs. stranded wire, and for shielded vs. unshielded. As far as I can tell, they all work fine. Plugs are cheap, about $0.40.

If you want to be fancy, you can buy little rubber "boots" to cover where the wires go into the plugs, in various colors for about $0.40. I don't bother, though they prevent breaking off the little plastic latch, which is nice.

A hub to plug everything into

For simple nets you won't need a filtering bridge or router, just a plain unfiltering hub (though if you've got a DSL or cable model connection, you may want one as a firewall. In large nets routers are crucial so that heavy internal traffic in one group doesn't slow down people in other groups. Hubs can be added most anywhere, and are a great way to save on extra wiring.

Hubs are available cheaply from most any computer mail-order house, or a good local shop. Get more ports than you need now. Hubs can be 10Megabit per second, or 100, or able to auto-switch between the two; I use a 10MB, 8-port hub I got for under $50.


A friend (Richard Ristow) once gave me a bit of advice on tool-buying that I recommend to you: "Buy the cheapest tool that is clearly better than what you need." For this work you'll need:

  • A modular plug crimping tool. Phone ones won't do it.

  • A cable tester. Don't skip this. I use the Progressive Electronics 468T and the matching receiver. Wire an Ethernet plug to some alligator clips and you can use the tester for lots of other things too (but don't try it on live power circuits!).

  • An inductive signal tracer is also a really good investment: you clip the tester on one end of a wire, and the tracer lets you follow the wire even hidden behind walls, or obscured in bundles.

  • A cable staple gun. I put off this purchase far too long.

  • Cable-labelling tape. 3M's Write-On Tape System is nice (Jensen catalog #649-333, $23.50)

  • Typical stuff like screwdrivers, wire cutters, pliers, sledgehammers, etc.

  • Safety glasses, dust mask, gloves, and other safety equipment as appropriate. Easy to skip; I did once and ended up with a dozen trips to the eye doctor.


How to do the wiring itself

Pick a location for your hub, preferably centered to keep cable runs shorter. A basement wall not too close to your electrical panel, or a wall in a closet, is useful. It may save you a lot of wiring if you use different hubs on different floors: weigh your time and the cost of wire, versus the cost of an extra hub(s).

Map out your wiring plan and decide how many wires go to each place. You may want to pull cable TV, phone, audio, intercom, etc. at the same time. If I'm going to go to much trouble, like fishing wires from basement to attic to wire a second floor, I pull more wire than I need and also leave a string in to pull more later. Wire is far cheaper than labor. You may want to install flexible conduit ("blue pipe") if you anticipate adding wires later.

Figure out how you will get a wire(s) from each place you want a connection, to the hub location. This may involve painful vertical runs, slogging through attics full of fiberglass dust (don't skip the mask!), drilling through walls and sole plates, etc. If you've got more than one floor, consider putting plates directly above each other to save on vertical drilling.

Plan wire placements to avoid anything that puts out much of a magnetic field. Stay at least 6" from electrical wires if running parallel to them.

Make a materials list and then order materials. Plan to leave a couple extra feet at each end of each wire run. Buy at least 10% more of everything (especially wire) than you think you'll need.

Start getting wires in place. Use staples to support long runs and to ensure gradual rather than sharp curves (don't staple if you don't have to, and be careful not to crush the wire). Do not pull hard on the wire, stomp it, crimp it, bend, fold, spindle, or otherwise mutilate. You can easily make the wire no good for 100MB with no visible sign of damage. If you put a staple through it, plan on replacing the run (theoretically maybe you could splice it; I doubt it's worth trying). Start with the longest runs first: that way if you do damage a wire, you have a better chance of cutting out the damage and having enough to be useful for a short run later.

It's best to finish each cable and test it before going on to the next. If fact, test the first end of each cable before bothering with the second end; this can detect a shorted cable and save time and connectors. Put a socket on the equipment end, and a plug on the hub end of each cable:

Install sockets at the device ends (typically wall-plates all over). Don't strip the wires. Remove only as much outer cover as you need to do the connections. If you're new to this, practice on scrap cable until you can cut the outer insulation without nicking the inner insulation. The best bet is to cut only partway through, and pull to snap the last little layer. Next, sort the wire ends into the right order for the socket. Untwist each pair just enough to get the wire ends all even, and never over 1/2 inch. Then trim the ends to be of the same length. Don't let copper hang beyond the ends, it can easily bend a little and short out the cable. Then put each wire into the right slot on the socket and push it down. You can try to get them all lined up and then squeeze down the cover; I find it easier to punch each wire into its slot with a fingernail, so they hold better even before the cover secures them the rest of the way. Double-check which wire is which.

Plugs are a little touchier. Remove the outer cover about 1/2 inch. Adjust the length so there will be intact outer insulation under the strain relief once the wires are seated. The strain relief is a bit of plastic near the back of the plug that gets crimped down at the same time as the connector pins do (practice on scrap the first time). After removing the outer cover, sort the wire ends into the right order for the plug. Untwist each pair just enough to get the wire ends all even, and never over 1/2 inch. One trick is to strip a little more than you need, sort the wires into the right order, then trim them off evenly to the right length. Don't let copper hang beyond the ends. Right after trimming, use one hand to hold them straight, check the color order again, and use the other hand to slip the plug on. Look into the plug (normally transparent plastic), check that the wires are seated under the connector pins, and then put the crimp tool on and squeeze. The most common error at this point is probably putting the plug on upside down, which will swap the wire order and not work.

Remember to test the cable. But note that the 468T tester I mentioned above does not stress-test cables at high bit rates; it just tests that you've got all the connections right. A full-featured tester is expensive (as high as $5000), so if you're doing only a little of this then just resign yourself to replacing a wire or two later, or borrowing a tester from a friendly expert. If you're running only 10MB on CAT5 wiring, you'll likely be just fine.

Once you have all your cabling done, plug into the hub and go. Then comes the really arcane art of setting up your servers, DNS, etc., about which this document will tell you nothing. Sorry.

Detail checklist

  • Never pull CAT5 wire with more than 25 pounds of force.

  • Never step on or otherwise crush, kink, or crimp the wire (don't make staples or wire ties tight).

  • Never put a staple through the wire (you knew that, I'll bet).

  • Avoid periodic sags; if the cable must sag, vary the intervals.

  • Never bend CAT5 wire tightly around a corner; make sure it bends gradually, so that a whole circle would be at least 2" across. Watch especially when the wire comes out a drilled hole and turns; don't let knots or kinks happen even temporarily.

  • Don't put so many wires in any conduits that it ends up more than 40% full.

  • Never untwist the 2 wires in a single pair for more than 1/3-1/2" to make a connection (the twists are critical to cancel out interference between the wires).

  • Never run the wire parallel to power wiring nearer than 6" away.

  • No run (hub to device) may be over 100 meters long (if you had a 100-meter long house, you'd be hiring this done anyway!).



CAT5 connectors look just like telephone connectors, only slightly wider, to allow 8 wires instead of 6. You can physically plug a 6-pin plug into an 8-pin socket, but it may damage pins 1 and 8 of the socket. Ethernet only uses 4 wires, but running 8 will save enormous time the first time a wire fails: you can just switch to another pair. Also, if no wires break you can split out the 8 into two sets of 4, and put 2 devices at the end of any wire (there are even handy adapters for this, like a one-to-two phone line adaptor; sadly they're not easy to find, but you can make one with a plug and two sockets). Or you may be able to use the other pairs for phone lines. However, I gather that the formal CAT5 definition reserves the remaining wires, so this is technically not allowed.

Or, in prose (and for accessibility), from pin 1 to 8 we have green/white, green, orange/white, blue, blue/white, orange, brown/white, brown.

Pair 1 is the blue pair, 2 is orange, 3 is green, and four is brown. So far as I know Ethernet protocols are not sensitive to insulation color, so if you scramble the pair assignments consistently you should be fine; but I wouldn't recommend it.

Only pair 3 (green, on pins 1 and 2), and pair 2 (orange, on pins 3 and 6) are actually used. So you can botch the other pairs and not get in trouble... until you want to use the other pairs to add a device without having to pull more wires through walls.

Old 10-base-t Ethernet specs called these pairs 1 and 2, on the apparent expectation that you wouldn't have any other pairs around. But pair 1 in CAT5 is the blue pair in the center, which is not used -- this is the same color and pins as for the primary telephone line wires, so avoiding it has the advantage of making it less likely that a telephone pair will get patched to an Ethernet pair (where the ringer voltage would probably cause lots of trouble).

CAT5 signals are "balanced": the striped and solid wires in a pair carry the same information negated, so their magnetic fields tend to cancel. Unlike phone wires, CAT5 wires do not cross over; the same wires go to the same pin numbers at all connectors. This works because hubs all have internal crossovers. Hub-to-hub interconnects need a special crossover cable, as does a hub-to-DSL-router connection, or a 2-node hubless network..

Be very sure you count the pins in the right order. Some connectors do not have pin numbers marked, though some are even better and are color-coded directly for T568A and/or T568B. If you get things backward they won't work (well, if you get everything consistently backward, maybe). You cannot swap wires across pairs (for example, to treat green and orange/white as a pair), since they are not twisted together, which is critical.

Warning: some sockets do not have the connectors in pin order, apparently because the sockets include internal twists for the same reason cable pairs are twisted. Mine go 21354687; but they're color-coded so you can ignore the pin numbers entirely. Make sure.

  • If you're looking into a socket with the latch downward, pin 1 is on your left.

  • If you're behind the socket with the latch downward, pin 1 is on the right.

  • If you're looking at the contact end of a plug with the latch down, pin 1 is on the right.

  • If you're looking at the wiring end of a plug with the latch down, pin 1 is on the left.

(Hint: Engrave "1" over pin one of the sockets on your tester)

Alternate wiring

T568B is identical to T568A except that pairs 2 (orange) and 3 (green) are swapped. Thus the order is: orange/white, orange, green/white, blue, blue/white, green, brown/white, brown. This is very common, and interoperates fine with T568A (as long as each cable is consistent in itself!). To avoid confusion, I'd avoid mixing A and B in a single location.

USOC, says my chart, "is traditionally found in telecommunications systems". The sequence is: brown/white, green/white, orange/white, blue, blue/white, orange, green, brown. This will not interoperate with standard Ethernet cables or devices, since pins 1 and 2 aren't even a pair.

Crossover cables are used for hub-to-hub connections and for 2-machine networks with no hub (I carry one around for on-the-fly networking). Basically, a crossover cable swaps pairs 2 and 3 (not the wires within each pair); pairs 1 and 4 go straight through. This means one end is T568A and the other is T568B; there's probably some interesting history to that.

If you use a punchdown block, the convention is to punch down the pairs in numeric order. In each pair the striped wire precedes the colored wire. Thus white/blue, blue, white/orange, orange, white/green, green, white/brown, brown (or "BLOG" for short: BLue, Orange, Green (brown is the one left over).

Relation to phone wiring

It is tempting to use the extra pairs in a CAT5 wire for phone lines. This may work, but apparently violates the CAT5 rules. The technical issue involved would be "crosstalk", where signals in one pair induce signals in others. This could be a problem; when ringing, a phone line is carrying something like 90 volts, which generates a significant e/m field. I have not tried sharing the wires this way myself; if you try it, please let me know whether it behaves for you. My best guess is that at 10Mbps it won't matter, but at 100Mbps it very well may.

Older phone wiring often uses 4 wires, in an RJ11 jack that can hold six. Red and green are pair 1, the center 2 pins. Yellow and black are pair 2, the next pins out. A single phone line needs only pair 1. The usual mapping to new wire colors uses pairs 1 and 2 likewise. This means than they go on the same pins if you use T568B (which may account for that being so common even though T568A is said to be preferred):

   Red      Blue
   Green    White/blue
   Yellow   Orange
   Black    White/orange

Cable specifications

CAT5 wire is typically 24AWG solid copper with each pair twisted about 3 times per inch (actually, each pair is twisted at a different rate). You can get it with or without a foil shield, and in various outer insulation materials. You need the more expensive "plenum" cable if you're running the wire in certain places, such as heating system plenums or certain commercial settings; this is probably not needed for home use, but check your local fire and electrical codes to be sure.

Note that commercial patch cables are often made with stranded instead of solid wire; this apparently has lower high-frequency performance, so keeping patch cables as short as possible seems like a very good idea.

Home Depot and similar shops around here carry it in bulk at ok prices. I've seen ads for a nice combination cable for residential wiring: one wrap that includes 2 CAT5s, video, and some phone lines. Probably costs more and is obviously less flexible, but easy to pull.

One site I found gives this information on the electrical characteristics of CAT5 cable: Impedance: 100 Ohms, Frequency rating: 100MHz, Capacitance 13.5 to 17 picofarads per foot, Attenuation 23 to 67dB per 1000 feet, Crosstalk 32 to 51 dB at 1000 feet. I have no information on the signal characteristics used.


Connecting to DSL or cable modems

I'm right at the length limit for DSL, so had to learn a few tricks. For example, the provider's measurement of your distance out will likely be about 2000 feet too high -- merely plugging in the DSL modem may knock 2000 feet off the measurement (thus, perhaps, bringing you in range). Also, every splice in the line degrades the line -- especially things like wire nuts. It may help to install the DSL modem right where the line enters the house (in which case, be sure you've run a CAT5 line from there to your hub). My line was unreliable until they came in and removed 2 gratuitous splices.

Typical DSL and cable modems connect to the carrier on one side, and have a standard Ethernet connector on the other. Probably the Ethernet is going to be 10 Megabit, since that's still way faster than DSL or cable speeds. The modem is essentially a hub, with translation from Ethernet to DSL built in; once the modem is in, you should merely have to plug a crossover cable from it to your hub, and then have the fun of configuring. You should be able to hang printers and other devices on your internal net. But if you want more than one machine to have Internet access, you may need to do something special:

  • If your provider uses fixed IP addresses, you can get an address for each machine from your provider (probably at extra cost).

  • If your provider uses dynamically-assigned addresses ("DHCP"), you may be able to just plug in extra devices and they'll work. Or the provider may catch it and either refuse them, or quietly start charging you extra, or something.

  • Or, you can get a small routing box that you hook up as if it were a full-fledged machine. It takes the one IP address you have, and forwards messages back and forth between your other machines and the net. It will probably support DHCP on your side, so any machine you plug into your net gets assigned an IP address automatically (such addresses come from a reserved range that is just for internal networks -- so routers won't generally pass them through, and your internal traffic shouldn't be visible to your provider). The box then uses "IP masquerading" to rewrite requests from your machines and forward them onto the Internet as if they were its own (and of course to forward the replies back the other way).

Once you're connected, you're connected. Your machine is truly on the net; which is great since you get fast response and no setup time. It is also dangerous. A bug in any program you run (knowingly or not) that talks to the net, can expose your entire system to hacking. This is itself a good reason to put in a DHCP router as just described; it provides considerable extra protection.

One more thing to be aware of once you're connected via DSL or cable, is privacy. Your machine sends your IP address to every server you talk to, because the server has to use the address to send anything (like a Web page!) back to you. With a modem connection your IP address is only "you" until you hang up: then it gets assigned to somebody else until they hang up. With a fixed-IP-address cable or DSL connection, you're you: your IP address is traceable to you (though I doubt your provider would publish it freely). Even the most law-abiding citizen may find this of concern. There are many technologies to increase privacy, but most are not widespread.


Cat-5/5e/6 Cable Info

The Telecommunications Industry Association and ISO (International Standards Organization) will not have the Category 6 or Category 7 standards finalized until at least some time after the year 2000, but in the interim, there is a new version of Category 5 which uses all four pairs of wires to both send and recieve! The new version, is formally called ANSI/TIA/EIA 568A-5 or simply Category 5e. Category 5e operates at up to 350MHZ. It's speculated, by some, that 90% of properly installed and certified Category 5 installations will be able to handle Gigabit Ethernet without problems. To find out about testing your networks ability to handle Gigabit Ethernet, Category 5e and upcoming Category 6 and 7, go to For official information about Category 5, 5e, 6 and 7 go to TIA's website. Gigabit Ethernet information is available at the Gigabit Ethernet Alliances website . There are some great articles about Gigabit ethernet over CAT5 cable in the August issue of Network Magazine!
Visit Cable University - "Your best source for training and technical support on communications cabling."

How to make a CAT5 Cable.

A good CAT5 termination Provides a proper wire crimp, a wire insulation strain relief crimp and a cable strain relief crimp. Also important, is not unwinding the wires more than necessary, maintaining the twists as far as possible is important, but don't let it stop you from inserting the wires as far as possible. I've made a lot of these cables personally, and this is how I do it.
*Strip the cables Jacket back one full inch.
*Untwist the wires back to within 1/8" of the jacket.
*Arrange the wires in the order in which you want to crimp them, (ie. 568A, 568B, etc.) .
*Grasp the wires firmly, between your thumb and forefinger, flatten them, and even wiggle them a bit, to take out the curliness, (concentrate your efforts on the bottom 1/2") the wires must lay flat and together, aligned as close as possible.
*While holding the wires firmly, cut off the the wires 1/2" from the cables jacket (Cut the wires with some sharp wire strippers or even high quality scissors, avoid wire cutters that flatten the ends of the wires insulating material, this makes stuffing the wires very difficult.)
* Stuff the wires into the connector, making sure the wires stay lined up. * The wires should reach the end of the little tube they are in, if possible, or at least past the farthest point of that "little funny Gold Plated thingy"above it, which will terminate it.
* The jacket should go even with the end of the first indent, if possible, it's a strain relief for the cable.
*Insert it into the crimping tool, and Crimp it! All of this is very dependant on the tools you are using, the connectors you are using, and the cable you are using. A bad combination can be hell!


How to wire a CAT5 (EIA 568-B*) Cable.

connector #1
connector #2


How to wire a CAT5 (EIA 568-A*) Cable.

connector #1
connector #2


*The only real difference between 568A and 568B is that
the White/Orange-Orange/White and White/Green-Green/White pairs are swapped.

Crimp strain relief:
Cable jacket should be inserted past the strain relief crimp.

How to wire a "Crossover" Cable.
(EIA 568-B*)

connector #1
connector #2


USOC crossover cables are like this:



color abbreviations:

The first color listed in the color pair is the dominant color of the wire.
In other words, WHT/ORG is a white wire with orange stripes.


9 Pin Serial Port Connector
9 pin "D" connector
Connector may be reversed depending on which side is viewed. All pins are numbered.
Pin No. Function Pin No. Function
1 DCD (Data Carrier Detect) 6 DSR (Data Set Ready)
2 RX (Receive Data) 7 RTS (Request To Send)
3 TX (Transmit Data) 8 CTS (Clear To Send)
4 DTR (Data Terminal Ready) 9 RI (Ring Indicator)


GND (Signal Ground)


25 pin Parallel Port Connector
25 pin "D" connector

Connector may be reversed depending on which side is viewed. All pins are numbered.

Pin No.


Pin No.





Auto Feed


Data 0




Data 1




Data 2


Select In


Data 3




Data 4




Data 5




Data 6




Data 7












Paper Empty






RJ45 Network Connector


Pin No.

Wire Colour




Transmit Data+



Transmit Data-



Recieve Data+









Recieve Data-








VGA Connector
15 pin High Density "D" connector

Connector may be reversed depending on which side is viewed.

All pins are numbered.

Pin No.


Pin No.


Pin No.



Red Video


Red Ground


ID0 (Ground)


Green Video


Green Ground


ID1 (No Connect)


Blue Video


Blue Ground


Horizontal Sync




No Connect


Vertical Sync






No Connect


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