These are based on the construction of the cable itself. There are F/UTP (a foil shield around a UTP cable), S/FTP (pairs in metal foil with an overall shield), and F/FTP (foil around foiled pairs).
STP cables are known are Sheilded Twisted Pair cables, STP cabling includes metal shielding over each individual pair of copper wires. This type of shielding protects cable from external EMI (electromagnetic interferences). e.g. the 150 ohm shielded twisted pair cables defined by the IBM Cabling System specifications and used with token ring networks. STP cables are CAT 5, CAT 5E and CAT 6
Last Wiki Answer Submitted: October 15, 2009 10:14 pm by Carrie Higbie640 pts.