The Problem

• Alien crosstalk, or ANEXT, is the major form of interference Category 6 cables suffer from. Like any copper cable traveling over a longer distance, these cables form a basic antenna, attracting other signals that you do not want on the cable. Alien refers to the crosstalk interference generated by adjacent electronic equipment, not within the cable itself. Thus the need for a shielded CAT6 cable is realized.
  
  

Unshielded Twisted Pair

• UTP CAT6 is a network cable type familiar to network installers. Consisting of four pairs of solid copper cables and a center plastic dielectric to keep them in place, UTP cabling tends to be less expensive that its shielded cousin. For most network applications where the cabling is kept reasonably distant from interfering equipment, UTP Category 6 is ubiquitous.
  
  

Shielded Twisted Pair

• In mission-critical applications, such as when the cable is feeding and surrounded by military and hospital equipment, shielded twisted pair is deployed. Virtually identical to UTP, STP is designed to be superior in preventing electromagnetic and radiofrequency interference from bombarding the cable pairs with competing destructive interference. This foil shield is surprisingly effective, given CAT6's ability to reach a 10 gigabit per second data rate.
  
  

Installation Considerations

• Modern shielded twisted pair cables do not require special grounding apparatus or termination processes, unlike older-style shielded network cables. Installers may test for ANEXT interference on UTP cables; however, this is not a necessary step for STP CAT6 wiring in most environments. A single ground, supplied at the central networking panel, is sufficient for STP wiring. Additional time is required for terminating shielded twisted pair, insofar as the shield requires some degree of separation from the wires prior to installing RJ-45 connectors.