WhatRoute is designed to find the names of all the routers an IP packet passes through on its way from your Mac to a destination host.
It also measures the round-trip time from your Mac to the router, thus enabling you to determine slow links or hops in the Internet. WhatRoute can also find dead links, such as routers that don't respond.
The software also uses a Geo-Location service to provide a geographical view of the paths that packets from your computer take as they traverse the Internet. These results may be passed to Google Earth for higher resolution display.