networking - ARP REQUEST 数据包中使用的发送方 IP 地址是什么？

Question

所以在一个ARP请求包中，我们有“Who has 192.168.1.1? Tell 192.168.1.143”。然而，回复不是“发送”到 IP 地址 192.168.1.143，而是发送到与其关联的 MAC 地址。拥有发件人 IP 地址的目的是什么？

谢谢。

Answer 1

这样人们就可以回复您而无需发送 ARP 请求。

一般来说the ARP rfc里面有很多多余的东西，但这件事情对我来说似乎没问题。

The sender hardware address and sender protocol address are absolutelynecessary. It is these fields that get put in a translation table.The target protocol address is necessary in the request form of thepacket so that a machine can determine whether or not to enter thesender information in a table or to send a reply. It is notnecessarily needed in the reply form if one assumes a reply is onlyprovoked by a request. It is included for completeness, networkmonitoring, and to simplify the suggested processing algorithmdescribed above (which does not look at the opcode until AFTER puttingthe sender information in a table).