What is the poll or quiz grace period for?

From Avacast Support

What is the poll or quiz grace period for?

Note that for simplicity, this article discusses the grace period in relation to polls, but the same information also applies to quizzes.

Whenever you run a poll in the Administrator and then it ends (either by reaching the defined end time or by manually clicking the Stop Poll button), there is a secondary period of time that must expire before the poll is considered completely closed ("closed" means no more responses can be collected from those viewing the presentation in a Player). During this so-called grace period, you cannot run another poll or show the results for the poll that was just run.

So what is this grace period for? The grace period is needed to compensate for any media streaming delay experienced by users viewing the presentation. The amount of this delay can vary quite a bit, usually in the range of 5 seconds to a minute, and depends on many factors, including the bitrate of the stream, the speed of the encoding computer, the speed of the end user's computer, and the network speed between the end user and the streaming source. And it will vary from user to user. Most presentation elements triggered by an Administrator (e.g. a slide change or a poll) must be delayed along with the stream, so that they appear on a user's computer at the correct point in the presentation (this is referred to as synchronization).

Going back to the Administrator for a minute, the Adminstrator starts and stops the poll in "real time." In addition, the results are sent in and gathered in real time. However, a user will see that same start and stop some time after the Administrator - the amount of time is determined by their Stream Delay. If the user takes a while to send her answer, it is quite possible that her answer will arrive after the the poll has already stopped in the Administrator, even though it appears to still be running in her Player. In this case, her answer will be not be recorded and will not appear in the results. However, by adding the grace period, Avacaster has extra time to collect and record these "late" answers.

Let's look at an example. Suppose you set up a 15-second quiz or poll and you decide that you want a 5-second grace period, because you find the extra closing time annoying. However, it is likely that this setup will not work well. If the user's streaming delay more than 20 seconds, they will not get a chance to answer your poll - they might see it flash briefly on their screen, or it may not appear at all. Therefore, this setting is not recommended unless you are using Multipoint or no media at all (audio-only streaming may work, but it depends on the circumstances).

By default, Avacaster defines a 40-second grace period, which may be longer than some user's stream delays. However, it was selected to accommodate as many scenarios as possible, since this value is defined server-side, meaning it is used by all presentations on that same server. As of Avacaster version 5.0, customers have the option of defining a different grace period for a particular event.

Of course, for those who are not using any media as part of their presentation, none of this matters. However, by default the grace period settings affects all presentations. Those customers who have their own Avacaster server may be able to change the default setting in the global settings files, which are located in Avacaster's SMUS directory - just edit poll_grace_seconds.txt and quiz_grace_seconds.txt. Other customers can use the custom option for event-specific grace periods mentioned above.