RJ14 and RJ11 pinouts?

[hkBattousai]

I have an ADSL modem. The modem is connected to wall outlet with RJ11 connectors.

**broken link removed**

The modem came with its own connection cable.
The cable has these pinout configurations:



Cable colors: https://en.wikipedia.org/wiki/Registered_jack#Pinouts
Cable colors:
End #1;
Pin #1 --> NC
Pin #2 --> Green
Pin #3 --> Red
Pin #4 --> NC
End #2;
Pin #1 --> NC
Pin #2 --> Red
Pin #3 --> Green
Pin #4 --> NC

But unfortunately, the cable is too short, and I want to crimp another one. I bought a new longer connection cable (only the cable, without connectors). It has four different colors in it. Namely; black, red, green, yellow.

Question 1:
Why red and green cables are reversed between the both ends in RJ11?

Question 2:
Are the pin configuration of red and green cables are the same in RJ14 as in RJ11

Question 3:
How do I connect black and yellow wires on the both wall outlet and modem sides in RJ14??

 

[hkBattousai]

I have found this relevant article:
Don't Do It Yourself PacBell DSL Page

It is discussed that the DSL line between the wall socket and the modem is always crossed.

Crossed RJ11 cable:
**broken link removed**

Crossed RJ14 cable:
**broken link removed**

My question is, when do we use a crossed cable, and when do we use a regular cable?

 

[Gary B]

Any time you are going from the wall to a telephone (or modem), you reverse polarity. That is true anytime you are using RJ11 or RJ12. If you are using the flat 4-conductor or 6-conductor cord, put the clip on the same side as the seam in the insulation and it will always be correct. This will change when you go to the RJ45 8-pin plug.

All other times with the exception of connecting two Ethernet ports without a switch, bridge or router you use a straight connection.

Those are used on the 4-pair cat5, cat5a and cat6 cables for Ethernet connections. There are two standards in use and you can use either as long as you use the same wiring on both ends.
Pin T568A T568B
1 W/G W/Orange
2 G/W O/White
3 W/O W/Green
4 Blue Blue
5 W/B W/Blue
6 O/W G/White
7 W/Br W/Brown
8 Br/W Br/White

By the way, just to confuse the issue, the phone company uses yet another configuration, RJ48C, for T1 and E1 lines.