10.23721/109/1353807University of Southern California-Information Sciences Institute, internet_address_census_it49w-20120731 (07/31/2012 to 09/02/2012)IMPACT2012en1353807292ping census of allocated IPv4 addressesTo collect this data, an Internet-wide IP address sweep was conducted. Every IP address in the ranges allocated by IANA was pinged once by sending ICMP ECHO_REQUEST (PING) packet. If the response (ICMP_ECHO_REPLY) came, its IP address was recorded in this data-set. In all, over 2.5 billion distinct IP addresses were probed during this experiment.