Are online and offline activations possible for the same license?

Yes, our Activation Server solution provides both online and offline activation.
The app connects via web services to the Activation Server to request for license activation. Here is a sample of web services provided by the server:
In case of offline, you can do it manually by logging on the server control panel:

Username: Administrator

Password: Administrator

Or, you can set up a web-based activation like the following sample page: