Contains the order in which an aggregation with a priority distribution is to be prioritized. If an aggregation has a distribution of Priority, then this resource SHALL be present. If an aggregation does not have a distribution of Priority, then this resource SHALL NOT be present. PriorityData SHALL be listed in order of priority, with the highest priority listed first. Note that if there are a large number of PriorityData, then this resource could grow large. Devices SHOULD use Range / Content-Range for transferring large resources as well as HTTP HEAD or other HTTP mechanisms to determine the size of the resource.<br/>