Gigablock Testnet Initiative Under Way – How Large Can Blocks Be?

Bitcoin Unlimited, nChain, and the University of British Columbia (UBC) have teamed up to bootstrap the Gigablock Testnet Initiative. The goal of the initiative is to determine how large blocks bitcoin can handle, and to analyze the bottlenecks that may impede bitcoin’s scalability.

According to a Bitcoin Forum post, the team has 4 main objectives with this project. They want to “setup and maintain a testnet network capable of supporting blocks up to 1 GB in size and sustained Visa-level transaction throughput (3,000 TPS).” They want to be able to experiment deeply with on-chain scaling to test its feasibility. They also hope to discover bottlenecks that affect scaling and then disseminate what they learn to the ecosystem.

Why Need a Gigablock Testnet?

The group is undertaking this project to finally determine how well large blocks can perform under a heavy load of transaction throughput. They mentioned that currently — as a result of small block sizes — transaction times and fees have become too burdensome. This makes micro-transactions impractical. The Bitcoin Forum article elaborated:

The Bitcoin network is currently plagued by record-high fees and unreliable confirmation times. For example, while fees of only a few pennies were sufficient in 2014 to get a transaction confirmed in the next block (~10 min), by June 2017 the average transaction fee had risen to $4 while the average confirmation time was over an hour. This has made using bitcoin as a means of payment impractical in many cases.

However, if the ecosystem is able to increase the bitcoin block size and make it reliable and workable, it could make bitcoin even more viable for mainstream adoption in the future. The Gigablock Testnet Initiative would also validate that it is possible to manage larger blocks, thus eliminating fear and argumentation within the community.

Project Duration and Work Completed to Date

The project is slated to run for 5 years. However, after the first 12 months, members of the project can vote to terminate it early. The initiative would then just be funded for an additional 3 months while the group wraps up operations.

Prior to the current initiative, Andrew Stone built the (NOL) No Limit test network in 2015. The site said Stone used the test network for the purposes of determining if Bitcoin Unlimited large blocks were feasible. However, the experiment was limited in scope and there was not enough data gathered. The current Gigablock Testnet Initiative represents a larger, more heavily financed continuation of Stone’s original experiments.

Challenges and Budget of the Gigablock Testnet Initiative

The article said the group could discover large blocks are impractical. They may realize VISA-level throughput transactions cannot be handled by the network, or the project is to vast to test in the time frame they allotted. They could also realize that “second layer” solutions are the only way forward for scaling the blockchain with current technology. However, they are optimistic their experiment will yield positive results for big blocks. The article read:

 We suspect this project will clearly demonstrate that Visa-level throughput can be reached and sustained on a global test network of mining nodes with today’s technology and for costs affordable to businesses, universities, and hobbyists.

The budget from BU is $150,000 per year, according to the article. The article explained the details, saying, “Nchain has agreed to match BU funds 1:1, giving a project budget of $300,000 per year for five years ($1.5M total project budget). Approximately half of the budget is expected to be used to cover server costs, while the other half of the budget is expected to be paid out as wages for contractors, employees and students.”