beautypg.com

H3C Technologies H3C SR6600 User Manual

Page 73

background image

65

Type Description

Category 5e

Suitable for data transmission at a maximum speed of 1000 Mbps

Category 6

Suitable for data transmission at a speed higher than 1 Gbps

Based on whether a metal shielding is used, Ethernet twisted pair cables can be classified into shielded

twisted pair (STP) and unshielded twisted pair (UTP). An STP cable provides a metallic braid between the

twisted pairs and the outer jacket. This metallic braid helps reduce radiation, prevent information from

being listened, and eliminate external electromagnetic interference (EMI) of external sources. STPs have

strict application requirements and are expensive although they provide better EMI prevention
performance than UTPs, so in most LANs, UTPs are commonly used.
An Ethernet twisted pair cable connects network devices through the RJ-45 connectors at the two ends.

Figure 48

shows the pinouts of an RJ-45 connector.

Figure 48 RJ-45 connector pinout

NOTE:

The RJ-45 Ethernet interfaces of the H3C SR6602 routers use category 5 or higher Ethernet twisted pair
cables for connection.

EIA/TIA cabling specifications define two standards, 568A and 568B, for cable pinouts.

Standard 568A—pin 1: white/green stripe, pin 2: green solid, pin 3: white/orange stripe, pin 4:

blue solid, pin 5: white/blue stripe, pin 6: orange solid, pin 7: white/brown stripe, pin 8: brown
solid.

Standard 568B—pin 1: white/orange stripe, pin 2: orange solid, pin 3: white/green stripe, pin 4:
blue solid, pin 5: white/blue stripe, pin 6: green solid, pin 7: white/brown stripe, pin 8: brown

solid.

Ethernet twisted pair cables can be classified into straight-through and crossover cables based on their

pinouts.

Straight-through: The pinouts at both ends are T568B compliant, as shown in

Figure 49

.

Crossover: The pinouts are T568B compliant at one end and T568A compliant at the other end, as
shown in

Figure 50

.