Monitoring Internet Reachability in Real-Time
What's the first thing you do when your Internet connection is not working? I changed my reasoning from thinking that it was related to my computer to one that assumed the Internet Service Provider was responsible for the outage.
Well that's not 100% true but I know several signs that tell me if it is my fault or the fault of my ISP.
I usually restart my router to be on the safe side but that's it. Sometimes you can make a connection to the Internet but that connection feels slow, you get disconnected regularly and websites may not be loading properly.
One way to find out if the problem is located on your side is to perform a tracert command to the target server. If that tracert times out you pretty much know the IP address of the server responsible for that along with information about the country the server is in. That is, unless the first hops time out already.
This is also the basic approach of Hubble, a service that monitors Internet reach-ability in real-time. Instead of using one tracert at a time they send out more than 100k every 15 minutes to monitor reach-ability problems throughout the world using a Google Maps mashup to provide a map of so called black holes, meaning servers that are unresponsive or have a reduced reach-ability.
The interesting information for the users are the IP addresses or ranges of those servers and the country column of the table. Sorting the column by country reveals problematic server at a glance which can help determining if the problem is located at your end.
Update: Hubble appears to be no longer available as a service that you can browse. The research behind the service on the other hand is still accessible on the Washington University website.
Update 2: The search is no longer available as well. You can however still read about it on the website to find out what it was all about.Advertisement