How to Big wall rock climb with proper back up knots

This is part of the How To Big Wall Book. In this segment Chris McNamara demonstrates how to use back up knots when jumaring. This is a technique video for summitting or sending problems on big walls outdoors. The knots are crucial for safe and effective rock climbing technique. When you are following in traversing terrain so that you are attached to the rope at more than one or two points. He is climbing El Capitan in this video.