Hi Jude,
To answer your questions, I would need to have some more information on the exact topology you are trying to use, and even in that case, the configuration would depend on your specific requirements.
With that in mind, I would recommend you to open a case with the PDI helpdesk team. They are specialized in helping out with design recommendations and new deployments so they are the right people to ask these kind of questions.
You can open the case with them through the link below:
http://www.cisco.com/web/partners/tools/pdihd.html
Regards
Daniel