Nasa didn't design it... it's actually a product of Canada.
http://www.forbes.com/global/2001/0219/061.html
http://www.nexiabiotech.com/en/00_home/index.php
Nexia Biotech is making a product they call "biosteel"... it's basically created by gene splicing the silk protein element from this south american spider into goats and then the goats milk contains this silk protein element which can be woven into the strongest fiber on the planet.
Sounds weird, eh? It's true. A 1" rope made of this material is strong enough to support the weight of a 747.