Hi
I would suggest to check out either CAR or class based policing for your requirement.
If u want to give a kinda gurantee to other classes of traffic (like voice,sap or JDE etc.,)would suggest to create different class for each traffic pattern and allocate the kinda gurantee as well the priority u require for those classes.
By default voice traffic has the privilege of being forwarded with high priority and the gurantee for other patterns follows accordingly..
do refer this link for more info..
http://www.cisco.com/en/US/tech/tk543/tk545/tsd_technology_support_protocol_home.html
regds