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為什麼192.168.0.0無法分配給設備？

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為什麼192.168.0.0無法分配給設備？

192.168.0.0 可以是網路位址，不能指派給本地網路中的任何設備。但為什麼？使用遮罩（如 255.255.0.0）的路由器無法找出網路位址嗎？

答案1

從http://web.archive.org/web/20100821112028/http://www.3com.com/other/pdfs/infra/corpinfo/en_US/501302.pdf（第 14 頁）：

《為每個子網路定義主機位址》 根據Internet慣例，IP位址的主機號欄位不能包含全0或全1。網路（或子網路）號。

更權威的是 RFC-943，位於http://www.ietf.org/rfc/rfc943.txt：

In certain contexts, it is useful to have fixed addresses with
functional significance rather than as identifiers of specific
hosts.  When such usage is called for, the address zero is to be
interpreted as meaning "this", as in "this network".  The address
of all ones are to be interpreted as meaning "all", as in "all
hosts".  For example, the address 128.9.255.255 could be
interpreted as meaning all hosts on the network 128.9.  Or, the
address 0.0.0.37 could be interpreted as meaning host 37 on this
network.

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