What Is The Difference Between Cat 5, Cat 5e, and Cat 6 Cable?
If you’re researching the different types of twisted-pair copper cable used to transmit data in network and home theater applications, then it’s likely that you will repeatedly come across the terms Category 5 (Cat 5), Category 5e (Cat 5e) and Category 6 (Cat 6). Organizations such as the Telecommunication Industry Association (TIA) and Electronic Industries Association (EIA) set specific product standards, and these guidelines have resulted in cables being classified into various categories based on their performance levels. Just in case you’re not too familiar with cabling terminology, we at CableOrganizer.com would like to provide you with a few straightforward definitions and statistics on these three common grades of network cable, to help you better choose the right one to fit your needs.
Cat 5: Out of the three types of cable we’ll be discussing, Category 5 is the most basic. Cat 5 cable is available in two varieties: Unshielded Twisted Pair (UTP), the type widely used in the United States, and Screened Twisted Pair (SCTP), which has shielding to provide a measure of extra protection against interference, but is rarely used outside of Europe. Cables belonging to Category 5 are either solid or stranded: Solid Cat 5 is more rigid, and the better choice if data needs to be transmitted over a long distance, while Stranded Cat 5 is very flexible and most likely to be used as patch cable. Cat 5 cable can support 10, 100, or 1000 Mbit/s Ethernet. The 1000BASE-T standard for Gigabit Ethernet over UTP was designed to work over up to 100 meters of plain old Cat 5.
Cat 5e: Cat 5e (which stands for Category 5, enhanced) cable goes along the same lines as basic Cat 5, except that it fulfills higher standards of data transmission. While Cat 5 is common in existing cabling systems, Category 5e has almost entirely replaced it in new installations. Just like Cat 5, Cat 5e can handle data transfer at 1000 Mbit/s, and is suitable for Gigabit Ethernet. Cat 5e experiences much lower levels of near-end crosstalk (NEXT) than Cat 5.
Cat 6: Of the three cable categories we’re discussing, Category 6 is the most advanced and provides the best performance. Just like Cat 5 and Cat 5e, Category 6 cable is typically made up of four twisted pairs of copper wire, but its capabilities far exceed those of other cable types because of one particular structural difference: a longitudinal separator. This separator isolates each of the four pairs of twisted wire from the others, which reduces crosstalk, allows for faster data transfer, and gives Category 6 cable twice the bandwidth of Cat 5! Cat 6 cable is ideal for supporting 10 Gigabit Ethernet. Since technology and standards are constantly evolving, Cat 6 is the wisest choice of cable when taking any possible future updates to your network into consideration. Not only is Category 6 cable future-safe, it is also backward-compatible with any previously-existing Cat 5 and Cat 5e cabling found in older installations.
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I would get a cable tester and double check the cable wiring - I posit that one of the wires is not punched down/crimped properly. Gigabit connectivity requires all 4 pairs work fine, while 100 megabit can run fine off 2 pairs. (I read your post, but it does not seem to me that you have tested the 20 meter cable on other hardware - that might be something else you wish to try)
I doubt it would be the case, but I guess it could also be an issue relating to crimping of the cable. You have not made it clear, but seem to imply you have a male connector on 1 end and female on the other - my understanding is that solid core is generally female to female, stranded core is male to male - and the connectors are designed differently with this in mind. I'd have expected this to reduce throughput but not stop negotiation at gigabit though.
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The tone generator only sends signals down a pair of cables. You need to send signals down all the pairs - all 4 pairs - to see where the break is. Because most cables are wired to 568B standards, there should be two pair of cable that are unused, and therefore, still viable - which means, you can relocate those strands to replace the damaged ones, and carry on. Simply repunch the cable on both ends with the dead pair swapped out and one of the two spare pairs put in its place, and you're golden.
(Yes, I know that technically you can just replace the one bad wire, but it's easier to remember the color coding scheme when you are working with pairs. And besides, the pairs are twisted, which means if it was a strain relief issue, the twin of the bad wire might also be marginal. That, and if you swap a single out instead of a pair, you defeat the purpose of the twist in the wire - which was to eliminate unwanted signals.)