There are two types of Radio Timeslot requests, earliest possible Timeslot requests and normal Timeslot requests.
Timeslots may be requested as earliest possible, in which case the timeslot occurs at the first available opportunity. In the request, the application can limit how far into the future the timeslot may be placed.
Timeslots may also be requested at a given time (normal). In this case, the application specifies in the request when the timeslot should start and the time is measured from the start of the previous timeslot.
The application may also request to extend an ongoing timeslot. Extension requests may be repeated, prolonging the timeslot even further.
Timeslots requested as earliest possible are useful for single timeslots and for non-periodic or non-timed activity. Timeslots requested at a given time relative to the previous timeslot are useful for periodic and timed activities, for example, a periodic proprietary radio protocol. Timeslot extension may be used to secure as much continuous radio time as possible for the application, for example, running an “always on” radio listener.