# What should be really have JOIN EUI? **URL:** \ **Category:** Uncategorized\ **Created:** [June 9, 2025, 1:47pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588 "2025-06-09T13:47:09Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![pierrot10](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/pierrot10/32/44794_2.png) [@pierrot10](https://www.thethingsnetwork.org/forum/u/pierrot10)\ **Post date:** [June 9, 2025, 1:47pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/1 "2025-06-09T13:47:10Z")
Hi, I am back with LoRaWAN after a long pause and I am going to install a irrigation station and a meteo station. Then I need to register two new station in a new application. I created the application and now I am create a OTAA station. I just observed DevEUI and I have no idea about the number I have to save. I look at my arduino file (for a previous station) and I can not find a similar information. I also understand that DevEUI replaced AppEUI. If now I look at my prevoious , I can see that I recorded the value ‘0000000000000000’. Even if all my 30 stations worked fine, I wonder if the value of 000000000000000 is relevent I can read in the black bulb where statnd the ? ![Screenshot 2025-06-09 at 15.37.00](https://www.thethingsnetwork.org/forum/uploads/default/original/3X/4/2/425a5f01616d3866f0f61481a5cdce4cf67f0548.png) As I developed my own station, I am concerned by the last section “What if I can not find the correct value”, then I supposed I can enter ‘0000000000000000’ but the black bulb also state > Ensure that you use the same JoinEUI in your end devise as you enter in the Thinks Stack As my stations have a unique ID and the new onw has the id 43, I wonder if the value of 00000000000000 is a good choose, even if it as been working. Would it be not better to have the value 0000000000000043? or it does nit matter? And then for my next own devise, I could have as a JoinEUI 0000000000000044? I also look at my new application (The Things Stack) if there is value with 16 digit, but none Many thank for this clarification ---
**Author:** ![descartes](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/descartes/32/47220_2.png) [@descartes](https://www.thethingsnetwork.org/forum/u/descartes)\ **Post date:** [June 9, 2025, 3:33pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/2 "2025-06-09T15:33:02Z")
> [@pierrot10](#): > > I also understand that DevEUI replaced AppEUI This is incorrect. It says in the info box “The JoinEUI (formerly called the AppEUI)” which is correct. Without knowing what firmware / stack you are using on your device, it’s hard to advise, but most up to date stacks can cope with all zeros for the JoinEUI and then you can get a DevEUI from the console and use that on your device. If you buy a device they normally come with a Dev & JoinEUI. The Learn section will explain the difference between ABP & OTAA and the different EUI’s & Keys you need for each setup. ---
**Author:** ![kersing](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/kersing/32/44777_2.png) [@kersing](https://www.thethingsnetwork.org/forum/u/kersing)\ **Post date:** [June 9, 2025, 3:35pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/3 "2025-06-09T15:35:48Z")
> [@pierrot10](#): > > that DevEUI replaced AppEUI It did not. The JoinEUI replaces the AppEUI. The DevEUI should still be a unique value for each device. You can ask TTN to generate one for you. For the Join/AppEUI you can use all zeros without any issues. Just make sure the DevEUI is unique. ---
**Author:** ![pierrot10](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/pierrot10/32/44794_2.png) [@pierrot10](https://www.thethingsnetwork.org/forum/u/pierrot10)\ **Post date:** [June 9, 2025, 8:41pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/4 "2025-06-09T20:41:00Z")
@kersing Oups, sorry. It’s my fault, I wanted to write JionEUI replaced AppEUI. Actually, I am using Arduino-LMIC. I understand that I could set 0000000000000000, but would it be a good idea to set 0000000000000041 for all stations for application1 0000000000000051 for all stations for application2 Same JoinEUI for all stations of the same Application? Otherwise, I will sett 0 etc… ---
**Author:** ![kersing](https://www.thethingsnetwork.org/forum/user_avatar/www.thethingsnetwork.org/kersing/32/44777_2.png) [@kersing](https://www.thethingsnetwork.org/forum/u/kersing)\ **Post date:** [June 9, 2025, 8:46pm UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/5 "2025-06-09T20:46:08Z")
> [@pierrot10](#): > > but would it be a good idea to set No it would not. There is no need to use anything but all zeros. Or an officially assigned (to your device) JoinEUI. ---
**Author:** ![system](https://www.thethingsnetwork.org/forum/uploads/default/original/3X/6/2/6250ea44fd2b0d6259489e1a92748df681e1f970.png) [@system](https://www.thethingsnetwork.org/forum/u/system)\ **Post date:** [June 12, 2025, 12:22am UTC](https://www.thethingsnetwork.org/forum/t/what-should-be-really-have-join-eui/71588/6 "2025-06-12T00:22:37Z")
This topic was automatically closed 24 hours after the last reply. New replies are no longer allowed.