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Cat 5e

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CAT 5E (Category 5 Enhanced)

Unshielded Twisted Pair cable (UTP) used for horizontal cabling within a Structured Cabling network (LAN).

The cable is made up of 4 pairs (8 wires) each wire being 24AWG (American Wire Gauge) in diameter and would be terminated onto an RJ45 connector. The cable's impedance is 100 Ohms.

The twists maintain the cable's characteristics and help to cut down attenuation and crosstalk. However on long runs the twists give rise to an effect called delay skew where the electrons arrive at the far end at different times due the twists increasing the length of certain conductors within the cables makeup. This stretches the signal which can cause DATA collisions increasing the error bit rate and effectivly slowing down the network (due to the rebroadcast of data packets).

In electrically noisy environments (e.g. on board a ship, in an aircraft), it is advised to use Cat 7 cabling because of its shielded nature.

Actually CAT 7 is not ratified by the TIA and if it is just a matter of shielding then shielded twisted pair (STP) or Foil Twisted pair (FTP) and if your hard core (get it!!) even Screened Twisted pair (ScTP) could be usedYou have to consider that the difference in Cat5 to 6 is the size of the conductor especialy as BSEN 50346 has incorporated TSB 95 and its extra testing parameters that have to be met when going for 1 Gig Ethernet. CAT 7 is about increasing speeds further but although 10Gig is working (in the lab) it is still too short in distance to be cost effective (compared to the now standard 90 metre footprint of horizantal cabling). If however the EMI of an installation was too great then we would push to Fibre Optic which is of course immune to EMI and has become very cost effective in the desktop cabling market especially with the likes of MTRJ and SC connectorisation.

Originally with CAT5 cable only 4 wires (2 pairs) were used. One being Transmit (TX) and the other Recieve (RX). By using all 8 wires (giving 2 TX and 2 RX) higher speeds were achieved but the effects of skinning became a barrier. An enhanced quality of copper gave rise to the CAT5E UTP cable and the concept of GIGA-ETHERNET became reality. CAT5E is now very cheap but has already been overtaken by CAT6 as the defacto UTP for new installations, due to the drop in costs in relation to future-proofing your network.

Yes Disco was here. And Gravelbelly couldn't resist adding to a stultifyingly boring entry (even if a littel iffy!, but he did write it down to impress down the pub.

Right. What you are trying to say, is that it's a bit of wire?

Yes. Go into PC World, ask for an Ethernet cable and they'll give you Cat 5.

And people have the gall to call us geeks. Anyone who can get this much text out of a bit of cat5e needs to get out more. Come on, i'll buy you a pint. User:Boney

OUTSTANDING. Award for the most boring entry in the ARRSEpedia. (Good CO)

Yes it's dull...but somehow rivetting at the same time... (Darth_Doctrinus)

(In the name of completeness:

Originally, Cat-5 was based on the EIA/TIA 568 Commercial Building Telecommunications Wiring Standard developed by the Electronics Industries Association as requested by the Computer Communications Industry Association in 1985)