Proration

1. The proportional distribution or allocation of parameters, such as noise power and transmission losses, among a number of tandem[?]-connected items, such as equipment, cables, links, or trunks, in order to balance the performance of communications circuits. Synonym budgeting.

2. In a telephone switching center, the distribution or allocation of equipment or components proportionally among a number of functions, to provide a requisite grade of service.

Source: from Federal Standard 1037C and from MIL-STD-188