internet_address_survey_reprobing_it47w-20120427 (04/27/2012 to 05/11/2012)

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, 40282 netblocks (/24 subnets) were periodically reprobed.为构建本数据集，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。若探测响应在11分钟的时间间隔内返回，则将相关结果记录至本数据集。该探测任务每11分钟重复执行一次，总计对40282个网络块（netblocks，/24子网）开展了周期性重复探测。