根據(jù)公安部制定的《GA370-2001端設備隔離部件安全技術要求》的定義，物理隔離的含義是：公共網(wǎng)絡和專網(wǎng)在網(wǎng)絡物理連線上是完全隔離的，且沒有任何公用的存儲信息。物理隔離部件的安全功能應保證被隔離的計算機資源不能被訪問(至少應包括硬盤、軟盤和光盤)，計算機數(shù)據(jù)不能被重用(至少應包括內(nèi)存)。
信息安全是一個體系防護的概念，網(wǎng)絡物理隔離技術不可能解決所有信息安全問題，但能大大提高網(wǎng)絡的安全性和可控性，能徹底消除內(nèi)部網(wǎng)絡遭受外部網(wǎng)絡侵入和破壞的可能性，從而大大減少網(wǎng)絡中的不安全因素，縮小追蹤網(wǎng)絡中非法用戶和黑客的范圍。目前存在的安全問題，對網(wǎng)絡隔離技術而言在理論上都不存在，這就是各國政府和軍方都大力推行網(wǎng)絡隔離技術的主要原因。
網(wǎng)絡隔離技術目前已經(jīng)發(fā)展到了第五代。第一代隔離技術實際上是將網(wǎng)絡進行物理上的分開，形成信息孤島;第二代采用硬件卡隔離技術;第三代采用數(shù)據(jù)轉(zhuǎn)發(fā)隔離技術;第四代采用的是空氣開關隔離技術;而第五代隔離技術采用了安全通道隔離技術?；诎踩ǖ赖淖钚赂綦x技術通過專用通信硬件和專有安全協(xié)議等安全機制，來實現(xiàn)內(nèi)外部網(wǎng)絡的隔離和數(shù)據(jù)交換，不僅解決了以前隔離技術存在的問題，還能有效地把內(nèi)外部網(wǎng)絡隔離開來，而且高效地實現(xiàn)了內(nèi)外網(wǎng)數(shù)據(jù)的安全交換，透明支持多種網(wǎng)絡應用，成為當前隔離技術的發(fā)展方向。
總的來說，網(wǎng)絡隔離技術的主要目標是解決工業(yè)控制系統(tǒng)中的各種漏洞：操作系統(tǒng)漏洞、TCP/IP漏洞、應用協(xié)議漏洞、鏈路連接漏洞、安全策略漏洞等，網(wǎng)絡隔離也是目前唯一能解決上述問題的安全技術。

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專業(yè)銷售進口DCS? PLC系統(tǒng)備件模塊