Help About the ANT Address Browser
Zoom, pan, and scroll using the controls (top left) and mouse (click and drag), like most other web-based maps.
To go to a location, click on the IP address bar and type in a hostname (www.isi.edu) or IP address (220.127.116.11). Pressing return will put a push-pin and scroll the map to that location.
The date selector moves the map in time, selecting a specific census date. Click the arrows to move earlier or later, or select a specific date from the drop-down menu.
We have taken data from several locations. Our main site is at ISI-w (ISI west in Marina del Rey, California, USA); we currently also take data from CSU (Colorado State University, Ft. Collins, Colorado, USA). In the past we also took data at ISI-e (ISI east, in Arlington, Virgina, USA). Finally, "whois", our address allocation data, comes from the five regional internet registries around the world.
Data from different locations may vary slightly because the Internet is always changing.
We plot several kinds of data: address responsiveness, round-trip times, organizations to whom the addresses are allocated. The kind menu selects between these data layers.
The responsiveness plane shows how many addresses in an area respond to our Internet census. We describe the census process and its validation on a separate page.
When each pixel shows many addresses, black areas indicate non-responses. When the map is zoomed in to show individual addresses, we switch to white to show a non-response.
The round-trip time plane shows how long replies to our probes take. Sites closer to our probers show up as light colors and white, while those far away show as darker gray. Since our probing sites are in the United States, European and Asian addresses are generally darker. However, comparing the ISI-w and CSU locations shows that even in the U.S., parts of the Internet are closer to Los Angeles or California.
The regional internet registries maintain whois data about to what organization each address block is allocated. They have agreed to provide these datasets to us so we may show them in our map.
Each organization is assigned a different (effectively random) color. Clicking on a spot or placing a push-pin shows address assignment.
The location plane shows geolocation (longitude, latitude) of addresses. Color is assigned to each pair of (latitude, longitude) by mapping longitude to hue and latitude to lightness in HSL color space. The result is that IP addresses in North America are roughly dark blue; magenta in South America; red-to-orage in Africa. Eurasia is dark red to maroon to green, and Australia is spring-green.
Right-click on a colored ip address or network to bring up a pushpin showing longitude and latitude. Sample Perl functions used to convert world-coordinates to color are available.
See something interesting? You can save a link to the map by clicking on the "Link this view" button. The URL in your browser's address bar will change to a URL you can cut-and-paste to share with others.
We hope you enjoy our Internet address browser. We welcome comments and questions; Please send comments about this web page to
For more information about our work, and for dataset availability, see our web page about address censuses.
(Back to the address browser.)