1. Jacobsen, V., et al.: traceroute. man page, UNIX, See source code: and NANOG traceroute source code (1989), ftp://ftp.ee.lbl.gov/traceroute.tar.gz , ftp://ftp.ee.lbl.gov/traceroute.tar.gz
2. Huffaker, B., Plummer, D., Moore, D., Claffy, K.: Topology discovery by active probing. In: Proc. Symposium on Applications and the Internet (2002), See also the skitter project: http://www.caida.org/tools/measurement/skitter/
3. Georgatos, F., Gruber, F., Karrenberg, D., Santcroos, M., Susanj, A., Uijterwaal, H., Wilhelm, R.: Providing active measurements as a regular service for ISPs. In: Proc. PAM (2001), See also the RIPE NCC TTM service: http://www.ripe.net/test-traffic/
4. McGregor, A., Braun, H.W., Brown, J.: The NLANR network analysis infrastructure. IEEE Communications Magazine 38, 122–128 (2000);See also the NLANR AMP project: http://watt.nlanr.net/
5. Cheswick, B., Burch, H., Branigan, S.: Mapping and visualizing the internet. In: Proc. USENIX Annual Technical Conference (2000)