This attribute specifies the emission priority to be assigned to
packets when this CoS Treatment is selected. The use of the
emission priority is egress media specific. This attribute can take a
value from 1 to 8. 1 is treated as the highest priority and 8 the
lowest. Some egress media support fewer then 8 emission prioritie.
For these media the values which correspond to emission priorities
lower then the lowest supported priority are treated as the lowest
priority. For instance, if a media supports two priorities, high and
normal, a vlaue of 1 corresponds to high priority and values of 2 to
8 correspond to normal priority.