Providing a solution to a Routing/ Scheduling Problem Before the advent of Informational Technology, routing scheduling was performed by experienced personnel (even now, in cases which can be handled by a experienced employee)
O Advantage of the experienced personnel were:
The good knowledge of the road network
The knowledge on traffic issues on the road network. Solutions provided are considered of high quality but... can only be provided for low-scale problems. So, large-scale problems, usually, are decomposed into smaller routing problems (i e. Geographical areas separation)
A large-scale problem enables a series of interfering parameters that are hard to be simultaneously taken under consideration by a person.
Some examples:
Public Bus Scheduling: More that 1000 routes (in a medium bus network) to be scheduled along with a crew with 1000 members.
Postman Routing Problem: in a high density urban area. COUR