I've seen Native Americans as great warriors who charged armies and raided settlements but I haven't heard much about their defensive capabilities. When they were attacked, did they have set up any stationary defenses (i.e. palisades)? Did they make use of any other inherent advantage of defense?
I assume you are talking about the 1720 to 1765 time period. If attacked by a superior force, the typical response would be to flee. The Indians did not use fortifications to any extent. They would hide their villages in inaccessible areas with approaches that were easily watched.