This attribute indicates the importance of the packets on the path.
Zero (0) is used for paths carrying the most important traffic, and
two (3) is used for paths carrying the least important traffic. In times
of congestion, the discardPriority is used by packet forwarding on
the trunk to determine which packets are discarded first to reduce
the load. Packets with a higher discardPriority (or numerically less)
are discarded after packets with a lower discardPriority (or
numerically higher).