Consider not to use port-forwarding at all
You already probably know we are not a big fan of port-forwarding for many reasons and that's why we had created much easier, secured and reliable way how to connect your cameras to the cloud (see Advantages of Angelcam Ready cameras).
But sometimes you just need to keep going with the hardware you had already purchased - and yes, we have a better solution than port-forwarding even for you, it's called the AngelBox.
Eliminating port-forwarding security risks
Do you still want to do port-forwarding? You can significantly lower the risk by limiting the access to open ports on your router just to the servers Angelcam is using to pull streams from your cameras.
For this reason we have created a semi-public table with a list of all IP addresses you can limit the access to. For security reasons, please reach us to get access to this list.
Once you have the access, you can use a built-in feature of a Google Docs to be notified anytime we update the list ("Tools -> Notification Rules").