herrold - ethernet punchdown

ethernet punchdown

EIA T-568A and T-569B
We wire T-568B everywhere -- when IPv6 is at 80 percent penetration, we will re-examine the A standard.

Diagnosis tip
A block wired A, with a B far end will show this pattern:

12345678	B master
78145236	A end

Pin Number Designations for T568B

Pin	color	pair	name
Color Codes for T568B
1	wh/or	2	TxData +
2	or	2	TxData -
3	wh/grn	3	RecvData+
4	blu	1
5	wh/blu	1
6	grn	3	RecvData-
7	wh/brn	4
8	brn	4

Note that the odd pin numbers are always the white with stripe color. The wires connect to RJ-45 8-pin connectors as shown below:

RJ-45 wiring for Ethernet (T568B standard)

The wall jack may be wired in a different sequence because the wires are often crossed inside the jack. The jack should either come with a wiring diagram or at least designate pin numbers.

Note that the blue pair is on the center pins; this pair translates to the red/green pair for ordinary telephone lines, which is also in the center pair of an RJ-11. (green=wh/blu; red=blu)

from: http://www.johnscloset.net/wiring/

Crossover Cable		Straight Through Cable
RJ-45 PIN	RJ-45 PIN	RJ-45 PIN	RJ-45 PIN
1 Rx+	3 Tx+	1 Tx+	1 Rc+
2 Rc-	6 Tx-	2 Tx-	2 Rc-
3 Tx+	1 Rc+	3 Rc+	3 Tx+
6 Tx-	2 Rc-	6 Rc-	6 Tx-

Note: The standard connector view shown is color-coded for a straight thru cable

Category 5 wiring standards:

EIA/TIA 568A/568B and AT&T 258A define the wiring standards and allow for two different wiring color codes.

Pin #	Signal	EIA/TIA 568A	AT&T 258A, or EIA/TIA 568B	Ethernet 10BASE-T 100BASE-T
1	Transmit+	White/Green	White/Orange	X
2	Transmit-	Green/White or Green	Orange/White or Orange	X
3	Receive+	White/Orange	White/Green	X
4	N/A	Blue/White or Blue	Blue/White or Blue	Not used *
5	N/A	White/Blue	White/Blue	Not used *
6	Receive-	Orange/White or Orange	Green/White or Green	X
7	N/A	White/Brown	White/Brown	Not used *
8	N/A	Brown/White or Brown	Brown/White or Brown	Not used *

from: http://www.makeitsimple.com/how-to/dyi_crossover.htm

Crossover pattern

from: http://www.derose.net/steve/guides/wiring/CAT5crossover.jpg

T-568B pattern

from: http://www.johnscloset.net/wiring/RJ45.gif

Patch cable end colors

from: http://www.makeitsimple.com/how-to/rj45colors.gif