[Filename] ca.key [Purpose] Root CA key [Secret] YES [Needed By] 
key signing machine only
s e r v e r + a l l c l i e n t s
k e y s i g n i n g m a c h i n e o n l y
s e r v e r o n l y
c l i e n t 1 o n l y
c l i e n t 2 o n l y
c l i e n t 3 o n l y