H3C MSR Router Comware 5 Series Manual page 168

Category-5 cables provide a transmission frequency of 100 MHz for voice and data transmission;
they are mainly used in 100Base-T and 10Base-T networks. Category-5 cables are common
Ethernet cables, which can also be used to transmit 1000 Mbps Ethernet data.
Category-5 enhanced cables feature low attenuation and crosstalk, providing higher attenuation to
crosstalk ratio (ACR), less delay error and higher performance than category-5 cables. Category-5
enhanced cables are mainly used in 1000 Mbps Ethernet networks.
Category-6 cables provide a transmission frequency of 1 MHz to 250 MHz, and improve the
performance on crosstalk and return loss. A fine better return loss performance is extremely
important for new-generation full-duplex high-speed networks. Category-6 cables have sufficient
power sum ACR (PS-ACR) when working at 200 MHz. They provide a bandwidth two times than that
of category-5 enhanced cables, thus featuring a higher transmission performance. Therefore,
category-6 cables are suitable for applications requiring a transmission speed of more than 1 Gbps.
The 10/100 Mbps Ethernet uses two pairs of cables, orange/white, orange, green/white and green
cables, to transmit and receive data, while the 1000 Mbps Ethernet uses four pairs of cables to
transmit and receive data.
For the pinouts of common twisted pair cables, see the following tables. (A and B represent the two
ends of a cable respectively.)
Table 216 Straight-through cable pinouts
Pinout No.
1
2
3
4
5
6
7
8
Table 217 Crossover cable pinouts
Pinout No.
1
2
3
4
5
6
7
8
A
Orange/white
Orange
Green/white
Blue
Blue/white
Green
Brown/white
Brown
A
Orange/white
Orange
Green/white
Blue
Blue/white
Green
Brown/white
Brown
159
B
Orange/white
Orange
Green/white
Blue
Blue/white
Green
Brown/white
Brown
B
Green/white
Green
Orange/white
Blue
Blue/white
Orange
Brown/white
Brown