internet_address_survey_reprobing_it29c-20091117 (11/17/2009 to 12/01/2009)

To collect this data, a subset of Internet IP addresses was pinged by sending ICMP ECHO_REQUEST (PING) packet. The response (if it ever came within 11 minutes time interval) was recorded in this data set. Probe was repeated every 11 minutes. In all, 22371 netblocks (/24 subnets) were periodically reprobed.为采集本数据集，研究人员通过发送网际控制报文协议回显请求（ICMP ECHO_REQUEST，即PING）数据包，对部分互联网IP地址执行PING探测。若目标地址在11分钟的时间间隔内返回响应，则将该响应记录入本数据集。探测操作每11分钟重复执行一次。总计共有22371个网络块（/24子网）被周期性重探测。