Frequently Asked Question
Port knocking is the process of sending tiny bits of data to certain ports in a specific order, sometimes with a specific payload, when the correct sequence is received, the firewall will automatically open the specific port or ports for you, and only for you. It's basically a tracking and matching system, no-one else can sneak in off the back of someone else's port knocking.
You also only have a small window of time to knock on each port, and all this must be done within an overall small time limit, if you're too slow, make a mistake in the port order if you're doing it manually, or your IP address changes, you'll have to start over again.
With our service, after successful port knocking, you have 30 seconds to connect to the service before the port is once again closed.
Port Knocking is available as an inbuilt function for the excellent Windows softphone, MicroSIP.
At present, when using a Mobile softphone App, you will require a third party App to do the knocking for you, some of these App's can open your softphone automatically once they have done the knocking, saving you from having to quickly open or change Apps yourself.
Port Knocker for Android - https://play.google.com/store/apps/details?id=com.xargsgrep.portknocker
KnockOnD for iOS - https://apps.apple.com/app/id333206277
On Android...
Open port knocker, press the plus symbol, you'll then be under a Host section, in Label, enter something to call the connection, eg: AIS, them select hostname and enter in the SIP Server hostname provided in your welcome Email.
Next swipe left, bringing you to the Ports section, enter in the port numbers as per your welcome Email and select UDP for each. (Well you didn't seriously think we were going to publish the ports we use publicly did you hehe)
Swipe left again and you should be in Other, tap on Launch Application and select Grandstream Wave, Zoiper, or your chosen Softphone App, you can leave the following two options as is, then tap the little icon that looks like a disk to save.
All you have to do now to connect is open the Port Knocker App, tap on your labels name, the App will knock and then load your softphone, a process that takes a few seconds.
On iPhones...
We don't have Apples here, but the KnockOnD iOS App is the closest we can find that's free and works, it allows you to enter a label Name to identify the task, and enter the hostname and ports, unfortunately, it does not let you configure an App to call, so you'll have to do some quick moves after running KnockOnD to load your softphone.