Once the scheduler daemon is running on a client, you establish a schedule
on the server for that client.  This is a two step process: 1) create a
schedule by selecting a time, startup window, action to take, 2) associate
a client or clients to that schedule.

There are two schedule modes, polling and prompted.  In polling mode, the
client periodically asks the server if there is anything to do.  This
occurs when the scheduler daemon is started and then on an interval of 12
hours by default.  This default can be changed in the client options file
with parameter: queryschedperiod in hours.  Once the client has gotten a
scheduled event, the client will start the operation at the time indicated
unless the client polls the server and gets a new schedule.

The other mode, prompted, has the server telling the client what to do at
the time of the schedule.  Polling is the default scheduling mode.  If you
want prompted, put schedmode prompted in your client options file.

The ADSM Admin Guide has a good description of all of this.