Are you sure its not 100m?You can get external ones and signal degredation starts to happen after around 30m (in an internal run) but you would probably be fine just using standard cat 5e ethernet cables outside. Obviously pay close attention to sealing where the cable comes back inside.
You'll probably find there is more damage done to the cable from UV rays by the sun than anything else, if you're fitting any cables externally just make sure and tie them in well so they're not flapping about too.
It's 100m (recommended 90 for fixed runs):Are you sure its not 100m?
The same applies for CAT6 (unless running at 10Gb where the max. length is less).According to the ANSI/TIA/EIA standard for category 5e cable, the maximum length for a cable segment is 100 meters (328 ft). If longer runs are required, the use of active hardware such as a repeater, or a switch, is necessary. This 100-meter limit is all inclusive. According to the standard, the practical limit for permanently installed cable is about 90 meters, leaving 5 meters at each end for the patch cables that connect the end equipment to the wall panel.