Table of Content

• What's the difference between Cat5, Cat5e, Cat6, Cat7, and Cat8 cables?
• How long can I go with Cat5/Cat5e/Cat6 cable?
• Which to choose: Cat5, Cat6, or Cat7 cable?
• What kind of connector does it use?
• What's the difference between 568A and 568B?
• Can I use a modular coupler to join two network cables?
• What are those plastic clips that came with my RJ-45 jacks?
• Why are the RJ-45 plugs I crimped failing?
• Why do some patch cables have boots?
• What's the difference between PVC, riser, and plenum cables?
• What's all this about twists (twisted pair)?
• What's the difference between unshielded twisted pair (UTP) versus shield twisted pair (STP)?
• What are 66 and 110 blocks?
• Isn't coaxial cable better?
• What is the difference between Cat-5 and Cat-5e?
• What is a crossed or cross-over Ethernet cable and how do i make one?

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What's the difference between Cat5, Cat5e, Cat6, Cat7, and Cat8 cables?

Each Ethernet network cabling designation essentially represents an improvement over its predecessor. For example, Category 5e (Cat5 Enhanced) offers better performance over Cat5. Typically, each version offers better shielding and faster data transfer rate than the previous version. The number of twists differ between each category of cables and typically, the higher the category, the more twists there are. The specification for each category is defined by the IEEE 802.3 standard.

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How long can I go with a Cat5/Cat5e/Cat6/Cat7 cable?

According to ANSI/TIA/EIA-568-A standard, "horizontal wiring" from a wiring closet to the outlet should be 90 meters or less, plus another 3 meters for a patch cord to the workstation. In round numbers, that's about 100 meters (328 feet).

If you plan to connect between buildings with different power sources, or go beyond 300 feet, you should consider using fiber optic line with a media converter at each end.

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Which to choose: Cat5e, Cat6, or Cat7 cable?

For most home and small office/home office (SOHO) networks, Cat5e should be your minimum. If you are building or upgrading your network, Cat6 is recommended. Cat6 is affordable and will provide the bandwidth headroom to handle additional network traffic in the future.

If you are a small- to medium-sized business with dozens of computer users and servers, Cat6 is the minimum recommendation. It is affordable and provide sufficient bandwidth for typical business network traffic. However, if your business handles large files on a daily basis, Cat7 is worth considering. It is pricey but you can benefit from faster file transfers to help ensure productivity.

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What kind of connector does it use?

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What's the difference between 568A and 568B?

TIA/EIA-568A and -568B are two standards for connecting Category 3 and Category 5 wire to connectors. Both are appropriate for high speed data, though 568B is somewhat more common for installed wiring and 568A is more common in jumpers. There is no performance advantage either way. The only real difference between the two is the order in which the pairs are used (orange and green).

Hold a cable as if to plug it into a wall jack, the locking tab down (contacts facing you). The contacts are numbered 1-8 from left to right. Here's what you will see:

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Can I use a modular coupler to join two network cables?

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What are those plastic clips that came with my RJ-45 jacks?

They provide some strain relief (so the wire doesn't pop out of the connection) and keep dirt and moisture out. They are not a replacement for using a proper punchdown tool to make the wire connection.

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Why are the RJ-45 plugs I crimped failing?

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Why do some patch cables have boots?

They look nice, and the companies that make patch cables can sell them for more money. Also, when you pull a cable back through a nest of other wires the boot keeps the locking tab on the plug from getting snagged and broken off. (That probably isn't a big concern for most home networks!)

Do boots keep dust out? Possibly, but a jack with a plug in it shouldn't be getting dust in there anyway... it's the empty jacks that collects dust.

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What's the difference between PVC, riser, and plenum cables?

The terms PVC (CM), riser (CMR), and plenum (CMP) refer to the jacket material of the network cables. It has no relation to the category of the cable (e.g., CAT5e, CAT7a) or its performance. These terms refer to the material used for the outer jacket of the cable to meet certain safety requirements.

Plenum rated cable is required by some fire codes if you run network cables in locations where the an air handling system moves air -- such as above suspended ceilings (plenum areas). Plenum cables are often used in commercial spaces and are designed to withstand higher temperatures than ordinary PVC jacket, burns less readily than PVC, and emits less toxic fumes when burned. Thus, if a fire does occur in an office, there is less chance of toxic fumes to circulate throughout the building. If an office building uses air ducts, plenum cables are may not required - check with your building or local city code on what's required.

Riser cable is a type of PVC cable and are designed for use in walls or in vertical cable runs between floors in non-plenum areas. Typically, they are install inside cable conduits and the jacket material is designed to minimize fire from spreading from one floor to another. However, the fire rating of riser cables is not as strict as plenum and thus should not be as a plenum substitute.

PVC (Polyvinyl Chloride) cable is what you you commonly buy for most of your home or office space networking cabling. These are often used in server rooms and network runs throughout office rooms. However, these are not fire-prone and thus should not be used in plenum spaces.

For most homeowners, plenum rated cable is not necessary and they typically costs two to three times more than PVC. There is no electrical or performance difference between the two and either will perform equally well.

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What's all this about twists (twisted pair)?

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What's the difference between unshielded twisted pair (UTP) versus shield twisted pair (STP)?

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What are 66 and 110 blocks?

Both are "punchdown" blocks used to interconnect voice and data systems in an orderly way. Type 66 blocks have been around longer and were developed for the phone company; they make it easy to connect multiple phone taps to a given line, and with the use of bridging clips provide an easy way to disconnect inside wiring from a circuit for troubleshooting. Older 66 blocks are not suitable for category 5 wiring, although several manufacturers have come out with revised 66 blocks that will work.

110 blocks are newer and are preferable for computer work: for one thing, they make it easier to preserve the twist in each pair right up to the point of connection. Most Category 5 jacks also use type 110 terminals for connecting to the wire.

A traditional impact punchdown tool with interchangeable bits like a Harris/Dracon will cost about $75 and can punch either 66 or 110 blocks (or any number of other types). Less expensive impact tools without interchangeable bits run about $25. Both kinds of impact tools both connect and trim the wire to the correct length. For a couple of bucks you can get a plastic tool for 110 blocks that might get you by for a few connections, but it won't trim the wire. Personally, I would stick with an impact tool.

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Isn't coaxial cable better?

Coax cable using the RG-58 connector for networking (Thin Ethernet or 10Base2) was common place in the 1980s and the early part of 1990s. However, the use of 10-Base2 today is limited. Organizations that still use this type of network cabling are doing so likely because their network equipment still employ it. The coaxial cable had a very high bandwidth capability at its time (10Mbps) with a maximum recommended length of 185 meters. However, majority of the network cable installation today uses the twisted pair Cat6 or higher network cabling.

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What is the difference between Category 5 and Category 5e?

Category 5e (Cat-5e) is an enhanced version of Cat-5 cable. The only difference between the two UTP (unshielded twisted pair) cables is the tested signal level. Cat-5e is tested at a higher frequency or signal level than regular Cat-5. This means with Cat-5e, you are getting a network cable that is tested under higher standards. With the price difference between Cat-5 and Cat-5e being minimal, its recommended to choose Cat-5e versus Cat-5.

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What is a crossed or cross-over Ethernet cable and how do i make one?

A crossed Ethernet cable is used for communication between two computers without using network gear such as a router, switch or a hub.

To identify a cross-over Ethernet cable, hold one end as if to plug it into a wall jack, with the locking tab down (contacts facing you). The contacts are numbered 1-8 from left to right. One end will have a different color sequence to the other. A crossover cable, like a straight through cable, works both ways.

In practicality, for straight-through cables, it doesn't matter what the color sequence is. It will still work and there will not be a degradation in network performance. However, from a design perspective, you should adopt one of the two standards and use it throughout your project. If you are adding network cables to an existing setup, follow the standard that's being used at the premise. In the majority of the cases you likely see EIA/TIA-568B being used.

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