HIP 58: PoC Distance Limit

• Author(s): @abhay, @mrpatrick1991, et al
• Start Date: 2022-04-02
• Category: Technical
• Original HIP PR: HIP: PoC Distance Limit #381
• Tracking Issue: HIP 58: PoC Distance Limit #384 (this)
• Status: Approved

Summary

The Proof-of-Coverage incentive model is crucial to the ongoing growth of the
Helium Network. As the network grows, efforts to prevent Proof-of-Coverage
gaming must be bolstered in order to encourage honest Hotspot deployment. One
known gaming technique works by altering the information provided by beacon and
witness packets to increase reported distances. This can make it appear that
Hotspots provide coverage where they do not. An effective way to reduce the
impact of this attack is to place an upper limit on the distance at which
witnesses for hotspots will be considered valid by the blockchain and thus be
considered for rewards.

When PoCv11 was developed, a witness distance limit feature was written but
never activated. If approved, this proposal would impose a 100 km limit to
Proof-of-Coverage witnessing and this value can be modified further through
governance in the future. Witnesses where the asserted distance is greater than
100 km would be marked invalid by the Challenger. This limit is further
supported by the fact that most sensor deployments have a practical maximum
distance of 30-50km. Although a Helium Hotspot may be able to see PoC beacons
greater than 100 km, there are no current use cases at this range.

Rendered View

https://github.com/helium/HIP/blob/main/0058-poc-distance-limit.md