Scheduling of delay-tolerant jobs has been proposed as a mechanism to alleviate pressure on congested network resources. However, when multiple competing users share these resources, they may not be willing to reveal the flexibility of the schedule for their jobs. This work presents a trading system that enables the users to trade their finite allowances in a scenario where they have fixed-size atomic jobs. The trading system makes it possible for tasks with strict timing requirements to be completed on time, while rewarding customers who exhibit flexibility regarding the schedule of their workloads (by reducing their operating costs or assigning them a larger share of off-peak capacity). The trading system hereby presented thus provides the right incentives so that user agents schedule their delay-tolerant jobs in a way beneficial for the whole system. It is proven to always converge, and simulations on real traces show significant reductions on the peak-to-valley ratio on the link utilization.