Establishing a Local Area Network (LAN) is based completely on the physical Ethernet cable. A LAN starts in the data room, a typical data room will have data racks holding servers, switches and patch panels.
The data racks can be wall mounted or free standing. Free standing vertical data racks are seven feet tall and are intended for a large capacity of switches and patch panels while mountable data racks are generally about 30 inches tall and mounted on to a backboard. Racks can be open, secure or convertible. Secure data racks are enclosed with a lock to protect the system from theft, tampering, or vandalism. Convertible data racks can either be open or secured depending on the accessories applied. After the data room, the cat5e Ethernet cable or cat6 Ethernet cable is run throughout the ceiling to specific locations in the building then dropped down the wall to be terminated onto a keystone jack. The cable used should be bought in bulk in boxes of 1000ft, having several boxes on the same job saves on time because if there are several drops going to a general area they can all be pulled at the same time along the same path and split up along the way turning a four cable drop into just one run. This makes it more convenient for the cabler and it also looks much cleaner when all the cables follow the same path above the ceiling.
Ethernet patch cables, whether they are cat5e or cat6, consist of four twisted pairs of wire which makes a total of eight wires within the cable. The four pairs are color coded as blue, orange, brown and green; each pair has a solid colored wire as well as a white striped wire. When terminating the cable to a patch panel, Ethernet jack, or even a 66 block there are two color patterns that are followed: 568A and 568B. Except for crossover cables, the pattern must be consistent on either end of the cable for the connection to work. Which pattern is used does not affect the cable as long as it is consistent, any pattern at all could be used but 568A and 568B are the two industry standards and no other pattern would be found in a professional installation. Cat6 Ethernet cable is becoming much more widely used than its predecessor cat5e. Cat6 cable has a tighter twist within the pairs which helps protect it from outer interference as well as improves performance up to 250 MHz, whereas cat5e has a performance capability of up to only 100MHz. The even newer cat6a (augmented), like the transition of cat5 to cat5e, has improved upon protecting the cables from interference and crosstalk but unlike the unchanging performance capabilities of cat5 vs. cat5e, cat6a is capable of performing up to 500MHz.