Communication cable is often distinguished by its Smoke Retardancy Characteristics. The three main categories are Communications Riser (CMR), Communication Plenum (CMP), and Communications Outdoor (CMX). The following table lists the most often used Cat5e and Cat6 cables explaining Ethernet Cable Specifications for both indoor and outdoor use.
Communications Riser / FT4
CMR is suitable in building risers and residential environments where fire requirements are not that strict. This is the most used cable for residential installations.
Communications Plenum / FT6
CMP is required when running cables in the plenum air space (plenum is the area above the drop ceiling that is used for HVAC air return) where fire restrictions are strict.
CMX is specifically designed for outdoor applications (Above Ground / Underground / Underwater). This cable is additionally protected by UV-blocking compounds.
UTP (Unshielded Twisted Pair)
Ethernet cable containing 4 pairs with no shield against electromagnetic interference.
STP (Shielded Twisted Pair)
Ethernet cable containing 4 pairs and a metal shield against electromagnetic interference.
Cat5e Ethernet cables carrying this frequency support 10/100BaseT as well as 1000BaseT, also known as Gigabit Ethernet.
Cat6 Ethernet cables carrying this frequency support 10GBaseT, also known as 10 Gigabit Ethernet.
The American Wire Gauge (AWG) specifies the thickness of the conductor in which the electrons flow. While a 24AWG with high quality copper and a very good twist rate may be able to provide the performance needed the EIA/TIA standards for Category 6 cables require 23AWG to assure performance without taking chances.