Twisted pair Token ring uses T568B pairs 1 and 3 (the same as T568A pairs 1 and 2), so a crossover cable to connect two Token Ring interfaces must swap these pairs, connecting pins 4, 5, 3, and 6 to 3, 6, 4, and 5 respectively.
A T1 cable uses T568B pairs 1 and 2, so to connect two T1 CSU/DSU devices back-to-back requires a crossover cable that swaps these pairs. Specifically, pins 1, 2, 4, and 5 are connected to 4, 5, 1, and 2 respectively.
Two pairs crossed, two pairs uncrossed
T1 crossover
Pin Connection 1: T568A
RJ-45 TIA-568A Left.png Connection 2: T568B
RJ-45 TIA-568B Right.png Pins on plug face
pair color pair color
1 2 Pair 2 Tip
white/orange stripe 1 Pair 1 Ring
blue solid Rj45plug-8p8c.png
2 2 Pair 2 Ring
orange solid 1 Pair 1 Tip
white/blue stripe
3 3 Pair 3 Tip
white/green stripe 3 Pair 3 Tip
white/green stripe
4 1 Pair 1 Ring
blue solid 2 Pair 2 Tip
white/orange stripe
5 1 Pair 1 Tip
white/blue stripe 2 Pair 2 Ring
orange solid
6 3 Pair 3 Ring
green solid 3 Pair 3 Ring
green solid
7 4 Pair 4 Tip
white/brown stripe 4 Pair 4 Tip
white/brown stripe
8 4 Pair 4 Ring
brown solid 4 Pair 4 Ring
brown solid
A 56K DDS cable uses T568B pairs 02 and 04, so a crossover cable for these devices swaps those pairs (pins 01, 02, 07, and 08 are connected to 07, 08, 01, and 02 respectively).
A T1 cable uses T568B pairs 1 and 2, so to connect two T1 CSU/DSU devices back-to-back requires a crossover cable that swaps these pairs. Specifically, pins 1, 2, 4, and 5 are connected to 4, 5, 1, and 2 respectively.
Two pairs crossed, two pairs uncrossed
T1 crossover
Pin Connection 1: T568A
RJ-45 TIA-568A Left.png Connection 2: T568B
RJ-45 TIA-568B Right.png Pins on plug face
pair color pair color
1 2 Pair 2 Tip
white/orange stripe 1 Pair 1 Ring
blue solid Rj45plug-8p8c.png
2 2 Pair 2 Ring
orange solid 1 Pair 1 Tip
white/blue stripe
3 3 Pair 3 Tip
white/green stripe 3 Pair 3 Tip
white/green stripe
4 1 Pair 1 Ring
blue solid 2 Pair 2 Tip
white/orange stripe
5 1 Pair 1 Tip
white/blue stripe 2 Pair 2 Ring
orange solid
6 3 Pair 3 Ring
green solid 3 Pair 3 Ring
green solid
7 4 Pair 4 Tip
white/brown stripe 4 Pair 4 Tip
white/brown stripe
8 4 Pair 4 Ring
brown solid 4 Pair 4 Ring
brown solid
A 56K DDS cable uses T568B pairs 02 and 04, so a crossover cable for these devices swaps those pairs (pins 01, 02, 07, and 08 are connected to 07, 08, 01, and 02 respectively).
A null modem cable.
An Ethernet crossover cable.