From 375e9378c974afed0e1565ff5c68edbeab957365 Mon Sep 17 00:00:00 2001 From: nejraselimovic Date: Sun, 15 Oct 2023 19:23:07 +0200 Subject: [PATCH] doc: Troubleshooting packet collision --- doc/content/devices/troubleshooting/_index.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/doc/content/devices/troubleshooting/_index.md b/doc/content/devices/troubleshooting/_index.md index 77e6d71e2d..c1689b26cf 100644 --- a/doc/content/devices/troubleshooting/_index.md +++ b/doc/content/devices/troubleshooting/_index.md @@ -215,3 +215,9 @@ Generally speaking, changing frequency plans in {{% tts %}} is not recommended a ## I see a "no decoder defined for codec {codec_id}" error after very downlink message. This error indicates that your end device was added from the [Device Repository](https://github.com/TheThingsNetwork/lorawan-devices), but in the device's codec file there are no `downlinkEncoder` and `downlinkDecoder` functions defined. To fix this, you can reach out to the device manufacturer to update your device's codec file in the Device Repository. Alternatively, you can define the [payload formatter]({{< ref "/integrations/payload-formatters" >}}) on your own. + +## Transmitting downlink message fails with the collision packet error. + +The `COLLISION_PACKET` error occurs when downlink transmissions overlap - this happens when two or more packets overlap in time and use the same spreading factor, bandwith and frequency plan settings. + +To avoid packet collisions, users can enable server-side buffering of donwlink messages. If server-side buffering is enabled, the Gateway Server schedules the downlink message to be sent after the downlink message that was already queued but not sent yet, so that their transmissions don't overlap. To enable this, navigate to your gateway's **General settings** section, expand the **LoRaWAN** section and **Enable** the **Schedule downlink late** option by ticking the box. Note that this is a recommended setting for gateways that use [UDP packet forwarder]({{< ref "/gateways/concepts/udp" >}}). \ No newline at end of file