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为什么无法将 192.168.0.0 分配给设备？

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为什么无法将 192.168.0.0 分配给设备？

192.168.0.0 可以作为网络地址，但不能分配给本地网络中的任何设备。但为什么呢？使用掩码（如 255.255.0.0）的路由器难道无法确定网络地址是什么吗？

答案1

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

“为每个子网定义主机地址 根据互联网惯例，IP 地址的主机号字段不能包含全 0 位或全 1 位。全 0 的主机号标识基本网络（或子网）号，而全 1 的主机号表示网络（或子网）的广播地址。”

更权威的是 RFC-943http://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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