网络通讯的七层定义及应用：1實體層 (Physical layer)2、資料鏈結層 (Data link layer)3、網路層 (Network layer)4、傳輸層 (Transport layer)5、會談層 (Session layer)6、展示層 (Presentation layer)7、應用層 (Application layer)-The seven network communication and application of the definition: 1 physical layer (Physical layer) 2, data link layer (Data link layer) 3, network layer (Network layer) 4, the transport layer (Transport layer) 5, talks layer (Session layer) 6, the presentation layer (Presentation layer) 7, the application layer (Application layer)