A:Answer The CAT versions are set by the IEEE organization. You might see manufacturing defects but in many years of working in the computer industry, I have not run into a factory made cable that failed to pass signal as intended.
Because copper wires can receive interference from electric wires and light fixtures, there are rules in which it should be run. If running along the side of 110/115v, it should be 1 foot away. If crossing 110/115v then you want to do so at 90 degrees. Florescent lights also cause interference.
The quality of your equipment can also determine the speed as does the length of the run. It does no good to buy a CAT 6 cable if any of your gear is rated at 100MB.
