DHCP concept

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DHCP 是什麼

DHCP (dynamic host configuration protocol)位於OSI七層模型中的應用層， 用來自動分配IP 位址給設備，讓設備可以簡單加入網路。


DHCP 的運行流程

買書的流程跟DHCP 運行流程類似

1. 在博客來書店查詢習慣（我感興趣的主題），相當于DHCP 運作流程的DHCP discover，發現在區網上的DHCP server 。

2. 回傳書名帶有習慣的書籍，在DHCP運作流程 這一步是DHCP offer 會回傳多個建議的IP 設定，因為區網上可能不只一台DHCP server 。

3. 選一本書加入購物車，在DHCP運作流程 為DHCP request ，表示已選一台DHCP server 。

4. 結帳後你就會取得這本書，在DHCP運作流程 為DHCP acknowledgement，會回傳給客戶端IP 位址、netmask、default gateway、DNS server等網路設定，客戶端就可以用這些設定來設定網路，並連上網際網路。

DHCP 運行流程
圖、DHCP 運行流程

DHCP觀念應用

用在整理上，先找（Find）出同類的東西（List），在一個一個拿起來細看（Closer look），哪些是準備要用的放在桌上（Dicide），不是馬上要用的放到鉛筆盒，鉛筆盒同類的只保留兩隻，這樣就可以保持桌面及鉛筆盒的簡潔。

DHCP 觀念用在整理
圖、DHCP 觀念用在整理



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