Amazon AWS tiered instances licensing model
On Amazon AWS Marketplace you can look for "OpenVPN Access Server". You'll see a number of results. Most of these include (xx connected devices) in the title. This indicates an image automatically licensed for the specified amount of connections when you launch it from the AWS Marketplace. This gets billed through Amazon directly. The costs are separated into software licensing costs and AWS instance costs, billed hourly. If you launch an OpenVPN Access Server (xx connected devices) type instance on Amazon AWS you incur charges for the use of the software and charges for the use of the instance you've launched while the instance is actively running. If you stop the instance, you stop incurring additional costs for the software licensing and running the instance. Some charges may apply for simply having the instance, like storage costs, but those are typically minimal. You could use such a system on demand if you wanted have an instance on cold standby ready to be launched when needed.
The OpenVPN Access Server for 5 connected devices comes with a temporary free trial. That means that when you launch it, for the first seven days, there isn't a software licensing cost billed to you. This allows you to test it out with five connections. You still pay for the infrastructure costs of running an EC2 instance on Amazon AWS, although you might be able to make use of the free trial options that Amazon AWS offers as well. If you're still running this instance after seven days, then the software license billing starts. Day eight will then be day one in terms of software license billing.
We also have an offering on the AWS Marketplace with no connected devices specified. This is our bring your own license (BYOL) image. This Marketplace image allows two concurrent connections when launched. To increase your connections, purchase an activation key from our website. This activation key gets billed by OpenVPN Inc. directly and doesn't get billed through Amazon AWS. The infrastructure costs for running an EC2 instance on Amazon AWS still applies and gets billed by Amazon itself.