RJ-45 cable wires...

[Total]

I just bought a RJ-45 24port Hubbell Patch Panel to mess around with.

I noticed that on the back only the 4 primanry Data In/Out wires are connected, the other 4 are not.

What are the other four strands in a RJ-45 cable used for and are they nesisary ?

 

[JackMDS]

NO

http://duxcw.com/digest/Howto/network/cable/cable5.htm

 

[Russ]

Like many things in this business, there is scalability built it. For now, though, they just look pretty.

Russ, NCNE

 

[ScottMac]

The concept of structured cabling extends beyond Ethernet networking.

The idea is to have one cable structure that will support nearly every possible (copper-based) need, from telephones to video to terminal connectivity.

For example, you can buy a BALUN that will let you transmit baseband video (the yellow RCA jack) and stereo audio over CatX UTP. You can send the output from your DSS satellite receiver to another room over UTP (and it looks pretty good), Lucent and others have BALUNs from transporting RF (like cable TV) over UTP (works OK if you have a good signal).

Other traditional uses include 3270 baluns for mainframe terminals, 5250 Twinax baluns, RS232 converters, intercom, phones, security cameras....all over the same high-quality UTP (Unshielded Twisted Pair).

In the networking environment, Ethernet uses two pair (1&2, 3&6), Token ring uses two different pair (3&6 & 4&5), ATM, and 56K digital uses two different pair (1&2 & 7&8), T1 uses two different pair (1&2 & 4&5)....so even though they're not all used all the time, having four pair available, each pair has slightly different transmission characteristics, makes the cabling system much more versatile.

In some situations, you can run two different signals through the same cable on diffeent pairs....but it's not recommended (like Ethernet on 1&2 & 3&6, then telephone down the

BTW: When you get around to installing the panel, and buying the "information outlets" to go with them, make sure you get the correct stuff. The panel should have some indication of whether it's rigged for "EIA/TIA 568A" or "EIA/TIA 568B." The "A" and "B" designation describes the pair order. If you have a 568A panel, and punch them to a 568B outlet, the orange and green pair will be swapped, and VV for B to A). Try to buy "B" outlets if you have a "B" panel, and "A" outlets if you have an "A" panel.

FWIW

Scott