首先，本文结合协同设计与分析支撑环境，从传输层、协作层和应用层三个层次分析并总结了协同设计领域中较完备的通信需求。
Firstly, with cooperative design and analysis environment, whole requirement is analyzed and summarized in the way of transport layer, collaboration layer and application layer.
首先，本文结合协同设计与分析支撑环境，从传输层、协作层和应用层三个层次分析并总结了协同设计领域中较完备的通信需求。
Firstly, with cooperative design and analysis environment, whole requirement is analyzed and summarized in the way of transport layer, collaboration layer and application layer.
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