By Jon Southurst,
Blockchain is improving its Thunder Network for faster settlement and refund times in off-chain transactions, according to a project update.
Stress Tests Underway
Released as an alpha-stage prototype for testing in May, Thunder is a version of Bitcoin’s proposed Lightning Networks, which handles transactions instantly between users and settles at a later time on the Bitcoin blockchain.
Solutions like this are intended to take some pressure off the main Bitcoin network, allowing a far greater volume of transactions of all sizes — while avoiding the politics of the block size debate.
Blockchain co-founder Nicolas Cary told Bitcoin.com his company is “currently stress testing the network and running internal code and security.” The focus is on hardening both the capacity and security of the network.
Cary said Thunder will move from alpha to beta phase when it’s ready for more testing.
Finding the Ideal Refund Mechanism
Processing off-chain transactions is not as simple as it sounds, so Blockchain is still testing new methods.
In the latest update, the developers talk about how Thunder handles payment refunds — important, since a key feature of Bitcoin is transaction finality.
Blockchain’s initial “dual-layer” approach to transactions meant that if a Thunder user wanted to claim a refund on a payment, they could be subject to lengthy delays — even up to a whole year — especially if one of the parties is offline for a length of time.
The company’s blog post explains it thus:
Dual-tx adds a second layer between broadcasting the settlement and claiming a payment which allows us to clearly separate the process of claiming a payment from waiting out the revocation delay. If the receiver of a payment wants to redeem a payment, he has to broadcast the second transaction which will allow them to claim the output of the second-tx after the revocation delay.
Problems arise, however, if one party to the transaction is dishonest and tries to cheat the system. Blockchain explained that the second transaction acts as a kind of safety net, allowing the party who actually broadcasts the initial transaction to claim a refund.
The counterparty can also claim a transaction directly from the originator’s payment channel.
This solution provides a 1-day payment window with a 2-week revocation delay, much faster than the existing implementation.
Please ‘Battle-Test’ Thunder
While it’s hoped Blockchain’s anti-cheating code never needs to run, Bitcoin and more general online services have revealed an innate human desire to game any new system for curiosity or profit.
Blockchain has done “rigorous unit testing in Thunder to cover all the cases of payments.” The code is open-source and the company encourages users to “battle-test” it.
A more technical explanation of how the layered-transaction system works is available on Blockchain’s site.