Arduino & Maxstream Xbee Zigbee

I am raised(brought up) French of high school diploma +2ans electrotechnics ( bts ) and we plan to realize the piloting of the street lighting through connection without son(sons,thread). We are convinced that the Xbee module will be for the height.

But can you say to me if the Xbee module possesses one programmable internal tempo or needs he(it) to add one?

Thank you in advance for the interest that to carry(wear) you to our project to finalize our studies :-[