What Is The Maximum Length Of Lightning To USB Cable Configuration For Tethering iPhone 5 To Computer For Internet Access That I Can Safely Use?

What Is The Maximum Length Of Lightning To USB Cable Configuration For Tethering iPhone 5 To Computer For Internet Access That I Can Safely Use?

IMPORTANT QUESTION......

The only Internet access I have is tethering my iPhone to my Mac Pro tower and using cellular data for Internet access.... So I use my iPhone 5 tethered or connected to my Mac Pro tower but the distance that it has to be is 15 feet....

Is it best to try to buy an single Apple certified off-brand 15 foot lightning to USB cable hooked directly from my iPhone 5 over to my Mac Pro tower or buy a powered USB hub and use the three-foot long lightning to USB cable from my phone to the USB hub and then from the powered USB hub 8 feet over to my Mac Pro tower.....

I want to use Apple manufactured cords because they are the best but they don't make a 15 foot cord should I buy a micro USB to lightning adapter and buy a second six-foot Apple lightning to USB cord or USB cord and try to make it work that way as a third option .....

I know the maximum length run for a USB cord is 15'5" but I'm not sure of the maximum length for a lightning to USB cord .....what is my best solution?