Copper wire is currently the most used medium for connecting computers and network equipment. Among its advantages are primarily low price and high enough speed that can provide data transmission. In addition, the material is flexible enough to be mounted in the walls and drawn by any office.
Over the last few decades have used several types of cable. In the past it was coaxial cable used (very similar to the TV antenna ), but lately has become the de facto standard twisted pair cable – UTP ( Unshielded Twisted Pairs ). Networks that use this type of cable has a star-type architecture because all computers are connected to a single device called hub or switch.
Interception of communications through copper cables do not present particular difficulties for professionals, based on the same principles with fixed telephony, but requiring acces to the physical cable. This last fact makes the interception quite rare because copper wire is generally used in offices where access is easily controlled .