https://github.com/hacash/paper/blob/master/tech/multi_layer_scaling_concept_definition.md
Why Need layer 3
Hacash's white paper points to layered scaling as the future of blockchain and offers a new type of peer-to-peer payment technology called layer 2, with layer 3 being proposed by the community.
layer-3-intro

https://hacash.com/
layer 3 Case
Currently Hacash layer 3 is mainly proposed by the Hacash.com team, and we can study it as a case study.
layer-3-case