Cat 6 Cabling
Category 6 is capable of transmission frequencies up to 250Mhz and has a positive power sum attenuation to crosstalk ratio upto 200MHz using improved cables and RJ45 connectors. The problem that manufacturers have, is that to meet the Cat 6 specification, requires the use of cables and connectors which are designed to work together as a 'tuned' system. This means that if you install a Cat 6 system the manufacturer will only guarantee performance if all of the components including the patch leads are from their Cat 6 product range. In fact, by mixing Cat 6 components from different manufacturers you could end up with a system with worse performance characteristics than a conventional Cat 5e system. That said, it is worth noting that Cat 6 systems are backwards compatible with Cat 5/5e cabling and when mixed with these lower bandwidth systems the performance criteria of the lower specification will still be met.