Upcoming Proof-of-Coverage Bug Fix
In the Helium Network, Proof-of-Coverage (PoC) is used to verify that Hotspots are providing wireless network coverage. Hotspots participate in PoC by issuing “challenge” packets using radio frequency (RF) signals. It is important that Hotspots are accurately representing their network coverage in order for the Helium Network to be useful for devices and applications.
After doing extensive statistical analysis on the behavior of the PoC algorithm, we recently discovered a bug that allows Hotspots asserted in incorrect locations to successfully participate in PoC challenges. In simple terms, a verification step that checks whether the RF signal matches what is expected for the claimed location of the Hotspot was being inadvertently skipped. This allowed Hotspots with incorrectly asserted locations to successfully complete PoC challenges when they shouldn’t have. In more complex terms, the RSSI signal check was being bypassed when PoC receipts were submitted to the consensus group for verification.
As a result, we will be deploying fix #593 which re-adds the correct verification step, and adds an additional signal to noise ratio and transmit frequency RF check as part of the verification process
Will this impact my Hotspot?
In our simulations we see that this will now cause Hotspots not asserted in their correct physical locations to begin to fail PoC challenges. Specifically, Hotspots that are co-located in a single location but have asserted locations spread out over a geographic area should expect the rate of PoC challenges succeeding to fall either substantially or completely. If your Hotspot is asserted within 100ft of its physical location, no action is required.
Note: This has nothing to do with your Hotspot’s GPS assertion status (e.g. good, bad, no fix, not asserted) as shown in apps like Sitebot.
When will this fix be deployed and do I need to take action?
We intend to deploy the code for this fix in an upcoming Hotspot OTA, but it will not be activated until Wednesday, September 16th at 12pm Pacific time. This should provide adequate time for any hosts that feel they may be affected to correct their deployments.
To update a Hotspot’s location, use the mobile app, find the Hotspot in the Hotspots screen, tap Settings, and press Update Location.
Join the Conversation.
If you have questions, please join the conversation on Discord to chat with the Helium community. We encourage any and all feedback and appreciate your support as these updates are made.
