Problem:

International standard ISO/IEC 11801 signifies general-purpose telecommunication cabling systems (structured cabling) that are suitable for a wide range of applications (analogue and ISDN telephony, various data communication standards, factory automation, building control systems). It covers both balanced copper cabling and optical fibre cabling. The standard was designed for use in commercial premises that may consist of either a single building or of multiple buildings on campus. It was optimized for premises that span up to 3 km, up to 1 km² office space, with between 50 and 50,000 persons, but can as well be applied for installations outside this range. A corresponding standard for small-office/home-office (SOHO) environments is ISO/IEC 15018, which also covers 1.2 GHz links for cable and satellite TV applications.
The standard defines numerous classes of twisted-pair copper interconnects, which diverge in the maximum frequency for which a certain channel performance is required.

a) Name and describe briefly the different classes?

b) The Same standard describes several classes of optical fibre interconnect. What are they?