What distinguishes FTP cabling from other twisted pair configurations, and what variations exist within the FTP category?

Q: What distinguishes FTP cabling from other twisted pair configurations, and what variations exist within the FTP category?   A: FTP (Foil Twisted Pair) cabling features twisted conductor pairs encased in an overall foil shielding layer, designed to minimize electromagnetic interference (EMI) and cross-talk in Ethernet LAN applications. Unlike UTP (Unshielded Twisted Pair) which lacks shielding, or STP (Shielded Twisted Pair) which uses braided screening, FTP balances cost and performance through its foil barrier.   Within the FTP category, key variations include: S/FTP (foil + braided double shielding for enhanced protection), F/FTP (individual foil-shielded pairs with an additional overall foil layer), and U/FTP (individually foil-screened pairs without an overall shield). These configurations are designated by standardized codes like F/UTP (overall foil/unscreened pairs) and SF/UTP (combined braided+foil shielding), catering to diverse EMI mitigation requirements in network installations.