KB76733091: WebCenter - Is the license released when you close the browser

Question

When you close the browser without logging out, WebCenter does not release the concurrent license until the session times out. Why is this?

Answer

WebCenter cannot detect that a user has closed the browser, as this does not send a signal to the web server (and that's the only thing WebCenter can react to).

When a user clicks Logout, a HTTP message is sent from the user's computer to the WebCenter web server. This releases the license (and does many other things too). However, when the user just closes the browser (or the tab containing WebCenter), no signal is sent and the web server does not know that the user no longer has an active tab to the WebCenter. 

We could create a trick to detect that people have left the application without logging out. However, such tricks are typically based on leaving a page, which is also done when navigating inside the application. So this will show a lot of false alerts, which are very irritating to the user (they would switch it off anyway). 

Notice that this situation does not create any technical issue. The web server is built to have lots of connections and having a set of inactive ones for a relatively short time is not a big issue (as long as these are real humans doing it and not some automatic system). 

Some customers indicate that this makes WebCenter more expensive. This however, is not true. The WebCenter pricing takes this effect into account. With a perfect logout mechanism, we would ask more money per concurrent user as the concurrency would be more idealized. Other web products work in very much the same way as WebCenter, this just follows state-of-the art techniques and pricing.