Abstract: In a Distributed Virtual Environment (DVE) system running on Wide Area Network (WAN), the control effect of causal order consistency is determined by both the correctness of causality and the real-time due to the large network transmission delay. In order to achieve a better trade-off between the quality of causal order consistency and real-time in a DVE, a new dynamic causal order control approach was proposed. The core idea of this approach was to dynamically adjust and balance the amount of blocked effect messages and that of delayed causal messages on each site in a DVE system, so as to meet the demands of causality correctness and real-time requirement on message ordering delivery. The evaluation results demonstrate that the proposed approach can outperform the previous ones by effectively improving the quality of causal order control while simultaneously preserving the real-time property of DVE systems.

Key words: Wide Area Network (WAN), Distributed Virtual Environment (DVE), causal order of message, consistency control, real-time

摘要： 在广域网运行的分布式虚拟环境中，由于消息传输延迟较大，因果消息序的一致性控制效果同时由因果序的正确性和实时性两方面决定。针对分布式虚拟环境消息序维护方法必须动态平衡因果序正确性和实时性的问题，提出了一种新的因果消息序控制方法，能够动态地调节和平衡分布式虚拟环境中各节点阻塞的结果事件数与延迟的原因事件数，满足因果消息处理的正确性和实时性需求。实验结果表明，与现有方法相比，该方法能够在保证实时性的同时，有效提高因果序维护的正确程度，为广域网分布式虚拟环境的消息序维护提供有力支撑。

关键词: 广域网, 分布式虚拟环境, 因果消息序, 一致性控制, 实时性