wall brick computer firewall network data block networksym communication Firewall Network Block Communication Data clip art 防火墙 网络 块 防火墙网络块通信数据剪贴画
A collection of graphics for creating context diagrams. Context diagrams are useful for modelling business operations and the scope of a system. 上下文 上下文关系图 数据流量 上下文图,数据流量图