Wi-Fi access points in Tokyo shared with blockchain

NTT recently experimented with sharing wireless access points in Tokyo, where there's a surplus of 20 times the amount needed.
12 May 2023

Wireless access technology in Japan is set to change. According to findings from NTT, Tokyo has approximately five million wireless LAN access points operating within its 23 wards. From a coverage point of view, this is 20 times more access points than are currently needed.

Wireless traffic in the city is expected to increase by roughly 80 times by 2030, relative to 2020. The increase could cause congestion and connection failures. To prevent this, it’s necessary to not only enhance individual Wi-Fi systems but also to secure radio resources for processing all wireless traffic.

Of course, this could be solved by installing more radio base stations as wireless access facilities on a grand scale, but building enough facilities to accommodate the increased traffic would be expensive. Needlessly so, given that the only barrier to using the existing surplus of access points would be an absence of profit incentive.

Private wireless access systems being used by individuals and businesses, like wireless LAN and local 5G, need to be more effectively used. When it comes to Wi-Fi sharing, the usual issues include:

  • How to provide an incentive to wireless access providers
  • How to ensure security in relation to sharing
  • How to reduce the costs incurred in system construction

Beyond these, other problems arise, even if wireless access sharing can be achieved. For example, if wireless access systems owned by a variety of parties are being shared, such systems will be individually operated instead of being centrally controlled, which means that users will end up connecting to wireless access systems with good communications quality in a concentrated manner, generating congestion.

That leads to more issues: a drop in usage efficiency and degraded communications quality for wireless access overall.

First successful shared wireless access points

Regardless of these roadblocks, NTT went ahead with an experiment to test the efficacy of network sharing. The scheme starts by asking operators of Wi-Fi access points or other connections if they are open to sharing their bandwidth and allowing random netizens to connect, in return for a share of the revenue from those connections.

Netizens search for available networks and, as they connect, a contract is executed, allowing a link to be made. That contract would use Ethereum Proof of Authority to verify identities and initiate the back-end billing arrangements before allowing signed-up users and devices to join private networks.

All participating network nodes “use blockchain-ledger information to smooth out the number of terminal connections in a decentralized and autonomous manner and improve communications quality,” according to NTT’s announcement of its trials. Those tests were conducted on “a mixture of wireless access systems having different administrators.”

If it works on a wide scale, NTT estimates Tokyo won’t need more Wi-Fi access points or private 5G cells, even as demand for connectivity increases. This means no commensurate increases in energy consumption – which is an economically and environmentally appealing result.

NTT hasn’t yet explained how it isolates transient connections from traffic created by an access point’s owner or operator. Customers might want this information before sharing connectivity, and the scheme will have to overcome other security objections about the dangers of using public networks; not even blockchain can erase all those issues.

Still, in a global first, the initial test of sharing technology using blockchain was a success. In theory, the eradication of individualized connection points could be adopted globally, at least in cities, saving the money that would have gone on constructing wireless access points subject to demand.