Firebind provides a straightforward way to verify whether your application will be able to successfully communicate to its respective server via your Internet connection. In order to prevent certain applications from being used, an Internet provider, whether it be a home broadband (Cable/DSL/Fiber) provider or corporation can block a given port or range of ports by creating a rule in their firewall. When you try to run your application, the firewall rule blocks the port to prevent you from reaching your server, but most applications aren’t able to provide feedback indicating why it is failing to work, leaving the user to wonder whether perhaps the server is down or maybe their client machine has some sort of problem.
Since virtually all firewalls will leave TCP port 80 (HTTP) open, Firebind uses that port to talk to its server and create a “listener” on the port the user is interested in. For example, if you are trying to test whether port 5190 is open for AOL Instant Messenger, Firebind will tell its own server to listen on port 5190, and will send traffic back and forth from your machine to our server on that port. If the traffic is successfully sent and received, it’s highly likely that the Internet provider is not blocking the use of your application. If the test traffic fails you’ll know immediately that the Internet provider is more than likely blocking the application.