Isn't this just a cellular mesh network? How does it compare to wifi mesh networking as far as range, security and usefulness? I'd like to see more of these decentralized alternatives to monopoly infrastructure providers, I'm just not sure how feasible they are.
LTE Direct is more about service discovery than data transfer.
As for mesh networking, it's hard. Routing becomes extremely complicated, especially when you're talking about mobile nodes. I used to work on protocol design for cognitive radios, where you have the added complexity of not having guaranteed spectrum. Mesh networks have certain advantages there,[1] but when we moved to a base station model things got exponentially simpler.
Distributed mesh networks are interesting in theory, but you have to be willing to pay a huge tax in terms of overhead and complexity.
[1] Say you have two nodes that, locally, never have common channels available. If you had a third node that shared at least one common channel with each, you could have it flip between the common channels to route data between nodes that otherwise can't talk to each other.
