What is a main difference between the edge routers and the core routers in the DiffServ architecture?

Question $57$Answer

a$.$

The latter are usually responsible for policing the flows while the former are usually not

b$.$

The former perform per$-$class traffic management while the latter perform per$-$flow traffic management

c$.$

The latter are usually responsible for marking packets while the former are usually not

d$.$

The former perform per$-$flow traffic management while the latter perform per$-$class traffic management