In order to satisfy the reliability requirement of high-layered systems and at the same time keep the kernel simple and efficient, we divide further the interprocess communication (IPC) facilities of the kernel into two layers.

• 为了能够既满足高层系统的可靠性要求,同时又保持分布式操作系统内核的简洁性和有效性,我们把内核的进程通信设施进一步分为两层。