>
> Is using different ports for CA and DRM (an so forth)  merely an 
> artifact of using multiple servers, or is there an additional  reason 
> to do so?
 Pkicreate tool allows selecting any ports.  Pkicreate also suggests 
 ports for out of the box ease of use. 
There must be more to the story than this.  I tried running pkicreate 
with two of the subsystems using the same port
-agent_secure_port=8443 -ee_secure_port=8443
And when it runs I get the error
[error] Invalid port numbers submitted!
Is there some reason that these cannot be the same port, or is it just 
convention.  Does the agent use some protocol other than HTTP?  I get 
this error is I try to use the same port for any two *_secure_port  values.