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CATEGORY CABLE MYTHS AND LEGENDS// Ralph Parrett - Liberty

Category Cables are twisted pair cables certified for performance to the ANSI/TIA/EIA-568C telecommunications standard.  The currently active levels are Categories 3,5e, 6, and 6A.  Each level is fully backwards compatible to the levels below it.  The frequency for each is listed in the chart below.  You will note there is no 350 MHz for Category 5e and there is no 550 MHz for Category 6.  That is because these are not official ratings.  Any values above the 100 and 250 MHz below have no basis in the ANSI/TIA/EIA-568C standard.  These are marketing efforts by manufacturers and distributors to try to show their cable is better than someone else.  Because values above the published standards are not regulated, a manufacturer can provide different results than the values that apply to the standard.  The ANSI/TIA/EIA-568C standard requires that the worst case results be reported.  However the sweep above the 100 and 250 MHz limit has no restriction set by the standard.  Because values above the published standards are not regulated, a manufacturer can provide different results than the values that apply to the standard.  They could report average values or best case values and inflate their perceived cable performance.  This game of 'Specmanship' can be annoying at best or undermine an install at worst.  Liberty's technical support team can help if you have any questions about the MHz ratings of our category cable, we supply both worst case and typical results for comparison.

Another item about the LAN program is that there is no Category 7 or Category 7A recognized by TIA/EIA.  However the European version of TIA/EIA - ISO/IEC 11801 does recognize and certify two constructions above Category 6A.  Class F cabling is called Category 7 informally and Class F_A is informally identified as Category 7E or Category 7A.