請問系統出現下列訊息代表的意義為何？

今天早上在root寄出的security run out put中出現以下訊息
請問代表什麼意義？

 Limiting icmp unreach response from 204 to 200 packets per second
 Limiting icmp unreach response from 258 to 200 packets per second
 Limiting icmp unreach response from 224 to 200 packets per second
Limiting icmp unreach response from 201 to 200 packets per second
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※ Origin: 雲林科技大學藍天使 <bbs.yuntech.edu.tw> [From: 219.71.24.146]