# Downlink messages limitations over TTN **URL:** \ **Category:** TTN Network and Services\ **Created:** [July 13, 2018, 2:14pm UTC](https://www.thethingsnetwork.org/forum/t/downlink-messages-limitations-over-ttn/15876 "2018-07-13T14:14:41Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![BoRRoZ](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/borroz/32/44234_2.png) [@BoRRoZ](https://www.thethingsnetwork.org/forum/u/BoRRoZ)\ **Post date:** [July 13, 2018, 2:22pm UTC](https://www.thethingsnetwork.org/forum/t/downlink-messages-limitations-over-ttn/15876/2 "2018-07-13T14:22:01Z")
> [@Fair Use Policy explained](https://www.thethingsnetwork.org/forum/t/limitations-data-rate-packet-size-30-seconds-uplink-and-10-messages-downlink-per-day-fair-access-policy/1300): > > For The Things Network’s public community network the [Fair Access Policy](https://www.thethingsnetwork.org/docs/lorawan/duty-cycle.html#maximum-duty-cycle) limits the data each end-device can send, by allowing: An average of 30 seconds uplink time on air, per 24 hours, per device. At most 10 downlink messages per 24 hours, including the ACKs for confirmed uplinks. A good goal is to keep the application payload under 12 bytes, and the interval between messages at least several minutes. An [online airtime calculator can give you some insight](https://avbentem.github.io/airtime-calculator). The following regulations apply a… --- _[View the full topic](https://www.thethingsnetwork.org/forum/t/downlink-messages-limitations-over-ttn/15876)._