# Does a node ever need to rejoin after OTAA? **URL:** \ **Category:** End Devices (Nodes)\ **Created:** [June 13, 2016, 8:41am UTC](https://www.thethingsnetwork.org/forum/t/does-a-node-ever-need-to-rejoin-after-otaa/2442 "2016-06-13T08:41:51Z")\ **Posts on this page:** 1\ **Showing post:** 4
**Author:** ![arjanvanb](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/arjanvanb/32/46626_2.png) [@arjanvanb](https://www.thethingsnetwork.org/forum/u/arjanvanb)\ **Post date:** [July 24, 2016, 1:05pm UTC](https://www.thethingsnetwork.org/forum/t/does-a-node-ever-need-to-rejoin-after-otaa/2442/4 "2016-07-24T13:05:48Z")
> [@catuin](#): > > can this be detected via the downlink response given by the backend …or _the lack of_ such response. When rolling out a lot of nodes we will (also) use the lack of some specific response (like receiving an ACK or downlink at least, say, every 48 hours), to start a join again. We want this to allow for switching networks: > [@How can an operational node be triggered to join a different network?](https://www.thethingsnetwork.org/forum/t/how-can-an-operational-node-be-triggered-to-join-a-different-network/1106/): > > I know “commonly used” is vague, but: do commonly used LoRaWAN modules/libraries (such as used in the TTN UNO) make it easy to change networks? For Over-the-Air Activation (OTAA) the LoRaWAN [R1.0 specifications](https://www.lora-alliance.org/portals/0/specs/LoRaWAN%20Specification%201R0.pdf#page=30) only define: An end-device has to go through a new join procedure every time it has lost the session context information. I guess an application could use a node’s downlink receive window to tell it to commence a new join procedure, or a node could do that when it’s not getting any r… --- _[View the full topic](https://www.thethingsnetwork.org/forum/t/does-a-node-ever-need-to-rejoin-after-otaa/2442)._