RJ45 Cabling Rules

1. Cable Length

In Fast Ethernet, cabling system must use Category 5 UTP or STP. The maximum length in a segment is 100 meters. The maximum diameter (in a collision domain) is 205 meters using two Class II hubs cascaded.

            

　

2. Phone Jack Pin Assignment

The pin assignment of RJ-45 connector must obey the EIA-568 standard. 

    EIA-568A Standard   

          

     EIA-568B Standard