This variable indicates the class of each kind of port on any kind of module for COPY PORT command at the module level. This MIB is defined for module level copy ports. This string is made of 16 bits. Each bit indicates a different class of ports. For example: P330 uses class A (1000...000) for all its ports. A P334T-ML will use class A (1000...000) for ports 1-24, class B (0100...000) for ports 25-48, and class C (0010...000) for ports 51-52.