Several core developers are seriously discussing the possibility of using rent fees to fund the continued presence of individual EDCCs on the Ethereum network. If a contract’s rent is not paid, it would become inaccessible, at least temporarily.
At a recent workshop in Taiwan, Ethereum developers, including Raul Jordan, Vlad Zamfir, Philip Daian, and founder Vitalik Buterin, discussed a "massive problem[1]" – that the network's current protocol offers no mechanism to finance the long-term storage of EDCCs, also known as smart contracts, on the base layer[2] blockchain.
At the moment, a user deploying an EDCC to the mainnet pays a one-time fee, yet all the network's nodes must store that piece of the network's state indefinitely. Jordan believes that rent fees must ultimately be charged, but in a way[3] that does not interrupt the "ability developers have to continue experimenting" with news Dapps.
In Buterin's words[4], "contracts that developers and users forget and stop caring about should disappear from the state by default."
For his part, Daian is emphatic[5] about the need to introduce a rent-collecting mechanism, arguing that "any system that provides a storage abstraction to its users must in some form or another charge rent." Though the cost of EDCC data storage on the mainnet is currently "subsidized by a commons-based storage model, in which the network bears the external costs of … smart contract transactions … in the long term," he does not believe that this scheme will serve the network well in the future.
Buterin came out with two related proposals for addressing these concerns. The first involves identifying the upper limit of how large the state of the mainnet should be allowed to grow (i.e., how much data it should be allowed to house), then establishing a fee structure that would prevent that limit from being exceeded.
He notes that with the eventual implementation of sharding[6], the fees charged in such a scheme would dip dramatically: post-sharding fees would be equal to the value of pre-sharding fees divided by the total number of shards.
In Buterin's model, any time a user sends a transaction related to a specific contract, or to data stored therein, they would "automatically pre-fill" that contract with rent fees that would enable it to remain operational for several years. The tokens paid in rent would be burnt. If a contract went down, other contracts which relied on it for data or for a functionality that it provides would be affected. Buterin also suggested that rent fees should be able to "decrease, but not increase," so that as hardware storage capacity goes up, the fees can fall accordingly.
The Ethereum founder admits that denominating the fees in Ether, as he proposes, could lead to them becoming unacceptably high, but adds that transaction fees are also subject to this uncertainty now
