Their are two standards for Ethernet CAT5 wiring. 568A and 568B. The wiring scheme he listed is 568B which seems to be the most popular. OW-0-GW-B-BW-G-BW-B
568A looks like this GW-G-OW-B-BW-O-BW-B The reason knowing and using the correct standards is important is that you buy gear such as patch panels or wall plates that may be 568A or 568B wired. I can't say that I've ever seen a manufactured patch cable not use 568A or 568B cabling. The standard is good because you can walk into a facility and not have to guess the color scheme in place. There is another advantage to sticking to the two standards. Should you need to create a crossover, simply wire one end 568A and one end 568B. Since ethernet only travels over positions 1,2,3 & 6 in the cable you can see that this will result in a proper crossover. If manufacturers are instructing cable construction any other way, they are wrong. Don't believe me, search the web! On Thu, Nov 08, 2001 at 08:24:57AM -0600, john beamon wrote: > Y'know, I almost hate to mention this, in case there are people learning > this for the first time. I've got installation instructions from certain > manufacturers and some prefab patch cables that start O-OW and end Br-BrW. > It's totally non-critical, since both ends are the same and the colored > pairs are in the same positions. It's just curious. > > -- > -j > > On Thu, 8 Nov 2001, Kris A. Wotipka wrote: > > > Date: Thu, 8 Nov 2001 00:20:51 -0600 > > From: Kris A. Wotipka <[EMAIL PROTECTED]> > > Reply-To: [EMAIL PROTECTED] > > To: [EMAIL PROTECTED] > > Subject: [brluglist] homemade CAT 5 > > > > Here is what a friend of mine here in Abbeville came up with. I'm not sure > > where he learned this but he is currently teaching the first two CCNA > > semesters at the local high school so maybe it's a CISCO thing. > > > > 1. Carefully strip the end of the cable being sure not to cut the > > insulation > > on the individual wires > > 2. Separate out the 4 pairs but do not untwist them. Place the O/OW pair > > to > > the extreme left and the B/BW pair to the extreme right. The other two > > pairs > > can go to the top or bottom. > > 3. Untwist the O/OW wires and straighten them out as much as possible. > > Place the OW to the left and the O next to it. > > 4. Untwist the G/GW pairs and place the GW next to the O. > > 5. Untwist the B/BW wires and place the B next to the O. > > 6. Place the BW next to the B and straighten them all out again still > > holding the jacked firm in the left hand. > > 7. Place the G wire next to the BW > > 8. Untwist the B/BW pair and place the BW next to the G followed by the B. > > 9. Straightening the wires as you place them provides a nicer grouping then > > if you untwist all the pairs at once. > > 10. While pinching the jacket with the thumb and index finger of the left > > hand, pull the grouping tight making sure that they all remain in order. > > 11. Trim them so that there is about 1/2 inch of wires protruding from the > > jacket. Make sure that the cut is even and perpendicular to the jacket. > > 12. Grasp the RJ-45 connector in the right hand, tab down and facing away > > from you. > > 13. Insert the wire into the RJ45 making sure that the grouping stays > > together and that the clamp portion of the RJ-45 is above the jacket of the > > cable. > > 14. Insert the RJ45 into a crimper and slowly squeeze the handle and hold > > for a ten count. > > 15. Test the cable by gently tugging on the end to make sure that it won't > > come off easily. Inspect the connector. Make sure that the grouping has > > not > > changed and that the cable clamp is crimped onto the jacket of the cable. > > Lastly check the cable with a commercial cable tester. > > > > > > hope this helps.......... > > > > kw > > ================================================ > > BRLUG - The Baton Rouge Linux User Group > > Visit http://www.brlug.net for more information. > > Send email to [EMAIL PROTECTED] to change > > your subscription information. > > ================================================ > > > > ================================================ > BRLUG - The Baton Rouge Linux User Group > Visit http://www.brlug.net for more information. > Send email to [EMAIL PROTECTED] to change > your subscription information. > ================================================ -- Scott Harney<[EMAIL PROTECTED]> PGP Key fingerprint = 6D 31 C3 00 77 8C D1 C2 59 0A 01 E3 AF 81 94 63 ================================================ BRLUG - The Baton Rouge Linux User Group Visit http://www.brlug.net for more information. Send email to [EMAIL PROTECTED] to change your subscription information. ================================================
