(Source1): All registered target networks from
Merit's routing arbiter database at ftp://ftp.merit.edu/routing.arbiter/radb/dbase/.
Full network scan (this graph uses data from 28 June 1999).
First, possible host names are generated
for all possible destinations
obtained from the routing arbiter database (Source1). Heuristics are used
to pick an IP address that is likely to be in use. A slow host scan over
time is then made until a responsive host IP address is found.
Finally, a set of UDP
probe packets are sent to each of these hosts, where successive packets
increment TTL by 1 until
a) the host is reached, b) an ICMP error is returned, or
c) a hop is reached that
doesn't respond to several pings.
Daily DNS reverse PTR lookups on any new addresses discovered (approximately 5,000/day).
Path database: Simple text format containing one
line per target network.
First field is the target network in familiar form: 18.104.22.168/16.
Remaining fields are in the form: name=[date:]value, and are used to
Path: a comma-separated list of IP numbers, followed by a status
code unless the path successfully reached the target.
Probe Date: Date of most recent probe
Target: date of first probe and IP address of responsive host
Whiner: date and email address of person requesting that this
network not be scanned
(Data2) Label Database: Simple text format. One entry per line
containing an IP number, a label, and the date it was collected, separated
by white space.
(Aggregate1): Various groupings of IP addresses can be derived.
For example, matching IP address octets to top-level domain can show approximate
country location, or, in this example, IP address octets are matched to second-level domain to show ISP names.
(Filter1): Edges may be removed.
(Filter2): Data may be reduced to show only shortest paths.