Android 平台ping 对方ip返回 +3 duplicates （重复回应包）

• DUPLICATE AND DAMAGED PACKETS

• The ping utility will report duplicate and damaged packets. Duplicate packets should never occur when pinging a unicast address, and seem to be caused by inappropriate link-level retransmissions. Duplicates may occur in many
• situations and are rarely (if ever) a good sign, although the presence of low levels of duplicates may not always be cause for alarm. Duplicates are expected when pinging a broadcast or multicast address, since they are not really

• duplicates but replies from different hosts to the same request.

• Damaged packets are obviously serious cause for alarm and often indicate broken hardware somewhere in the ping packet’s path (in the network or in the hosts).

• 大概意思：重复和损坏的数据包

• Ping将报告重复和损坏的数据包。当使用单播地址时，不应该出现重复的数据包，而且出现重复数据包似乎时是由不适当的链路重传引起的。
• 重复可能在很多情况下发生，而且很少（如果有的话）是一个好的现象，尽管低水平的重复现象不总会造成警报。

• 当在ping一个广播或多播地址时会出现重复包，因为他们不是真正的重复，而是来自不同主机对相同请求的是响应。

• 损坏包显然时可以引起严重的恐慌，通常指出在ping包的路径下哪部分硬件坏掉了（网络或主机）。