Queue Tree: traffic shaping: 4 Questions

Hey Folks,

Still trying to get my traffic shaper working well. Its objective is to assign priority to traffic NOT to limit speed. I simply want to say that SIP traffic has a higher priority than HTTP traffic.

I have successfully mangled the traffic to mark it.

I have a queue tree as per this image:
queue-tree.png
My questions are:

  1. Is PCQ the correct type of queue to use for this?
  2. What priority should be assigned to the parent queues?
  3. SHould I fill the Rate fogure in the PCQ queue types, or should I leave it blank?
  4. How can I test this QOS system?

Your help appreciated.

Alex