The necessary and sufficient conditions are given for the schedulability of real time connections at each network node under preemptive earliest due date scheduling policy.
在抢先最早预定日期调度策略下，给出了任意网络结点上实时连接调度能力的充分必要条件。
2
This method only needs computing the earliest start -time and the lastest finish-time of the node. Thus you work it out.