# Terminology for allocation of marginal inputs

Suppose there are four modalities 1, 2, 3, and 4, for moving goods between two particular destinations, with associated capacity $$\mathscr{C}_i$$ and cost $$c_i$$ for $$i\in \{1,2,3,4\}$$ and also that $$c_1. Suppose that there is demand to ship $$N$$ units of goods simultaneously and also that $$\mathscr{C}_1 + \mathscr{C}_2 < N < \mathscr{C}_1+\mathscr{C}_2 +\mathscr{C}_3$$.

It is convenient to assume that the system will behave as follows:

• Services 1 and 2 will be at full utilization, service 3 at partial utilization, and service C at zero utilization.
• If an additional unit of demand materializes, then service 3's utilization will increase by one unit.
• If service 1 increases its capacity to $$\mathscr{C}_1^\prime$$ and there is no cost to switch services, then $$\mathscr{C}_1^\prime-\mathscr{C}_1$$ units of goods will defect from service 3 to service 1, assuming that service's three's utilization is at least $$\mathscr{C}_1^\prime-\mathscr{C}_1$$.

So my question is, what is the terminology for this kind of model system and associated behaviors. Do you say that such a system is "Pareto optimal", for example?