nChain and Bitcoin Unlimited Launch Gigablock Testnet for Larger Bitcoin Block Sizes

The original Bitcoin (now more accurately described as "Bitcoin SegWit") network is currently plagued by record-high fees and unreliable confirmation times, which have impaired Bitcoin's ability to act as a worldwide payment system. To solve Bitcoin's current capacity problem, both nChain and BU share the vision to lift the artificial 1MB base block size limit, enable larger blocks, and achieve significant on-chain scaling of the Bitcoin network.  These are also goals of the Bitcoin Cash chain, which began (via an August 1, 2017 hard fork) with an initial default block size of 8MB and plans to lift the block size even further with appropriate testing.  Other proposed solutions, such as Segregated Witness (or SegWit 2x) adopted by the Bitcoin SegWit chain, merely defer the capacity problem.  With increased scalability via larger blocks, the network represented by Bitcoin Cash can power faster transactions, reduce fees, make confirmation times reliable once again, and achieve enterprise-level capabilities – cementing bitcoin's place as the dominant cryptocurrency.

However, critics of larger block sizes question whether the bitcoin network can safely and reliably handle the associated increase in transaction throughput if the block size is raised.   BU and nChain believe that the Bitcoin community needs scientific data, rather than theoretical arguments, to address those questions.  As previously reported, in July 2017, BU members met in Vancouver, Canada with representatives from nChain to explore ways in which they can collaborate to achieve larger block sizes and massive on-chain scaling of the Bitcoin network.  At that meeting, one proposal discussed was a global test network to identify bottlenecks to scaling and to conduct scaling-related research to determine the network's ability to handle significantly increased transaction throughput.  

After voting which concluded September 23, 2017, BU members overwhelmingly voted to approve the Gigablock Testnet Initiative (BUIP065). nChain and BU have committed to fund (50% each) a budget of up to USD $1.5 million over 5 years for the project.   BU will lead work on the project, with nChain providing both funding and staff support.  Although they are the project founders, BU and nChain intend for the Gigablock Testnet to eventually become a self-sustaining resource of the bitcoin community, with contributors from across the world. 

Specific objectives of the Gigablock Testnet Initiative are to:

• set up and maintain a global test network capable of supporting blocks up to 1 GB in size and sustained Visa-level transaction throughput (3,000 TPS) on the bitcoin network.  The plan is to add mining nodes in Beijing, Bangalore, Sao Paulo, Sydney and Vancouver, to expand an existing network of mining nodes in Toronto, Frankfurt, Munich, and Washington State. Transaction generators are also located across the world.  This larger Gigablock Testnet can be "stress tested" at very high levels of transaction throughtput; perform continuous experiments related to on-chain scaling on that test network;
• based upon the results of those experiments, identify bottlenecks and find ways to fix them ahead of time, in order to provide a safe path to larger block sizes for the bitcoin network; and
• disseminate those findings to the broader Bitcoin community.

BU has already created the new testing network, added mining and transaction generating nodes, and has begun carrying out its first planned experiment. 

In addition, the project will also receive assistance from the University of British Columbia in Canada.  Professor Victoria Lemieux at UBC will provide further research support where there are synergies between the University's "Blockchain UBC" project and the Gigablock Testnet Initiative. 

Andrew Clifford, President of Bitcoin Unlimited, observes:

"We believe the Gigablock Testnet Initiative will 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.   We anticipate that results from ongoing experiments carried out on this test network will add to the growing body of evidence that bitcoin can indeed scale into a functioning payment network for the world, following the design laid out in the original Bitcoin white paper written by Satoshi Nakamoto."

The Gigablock Testnet advances testing work already done by nChain and BU.  Separately, nChain has already been able to test 32MB blocks, and BU's "nolnet" testing network (led by BU developer Andrew Stone) has successfully tested 64MB blocks.  Such block sizes are already significantly larger than the current 8MB cap on Bitcoin Cash, and far larger than a recent Bitcoin SegWit main-net block of about 1.3MB.   BU anticipates that any scaling improvements realised through the Gigablock Testnet Initiative will be likely implemented first on Bitcoin Cash, given that chain's philosophy supporting larger block sizes. 

Stefan Matthews, Chief Executive Officer of the nChain Group, adds:

"Many people believe the bitcoin network can power faster transactions and enterprise-level capabilities.  At nChain, we put funding and action behind our beliefs, in order to make massive on-chain scaling a reality.  This Gigablock Testnet Initiative is also another step in nChain's growing collaboration with Bitcoin Unlimited. We hope our efforts with BU inspire even more bitcoin ecosystem players to work together – rather than fight each other - to advance bitcoin's role as the dominant cryptocurrency. We invite others interested in partnering with us to reach out to nChain."

In addition to its support of BU, nChain is researching and developing tools, protocols and applications to support blockchain growth worldwide. This includes a software development kit to enable programmers to develop applications on the Bitcoin blockchain, solutions for scalability of the Bitcoin blockchain, inventions to improve security, on-chain scripting for smart contracts and a decentralised trading platform that uses autonomous agents.

ABOUT NCHAIN: nChain is the global leader in research and development of blockchain technologies.  Its mission is to enable massive growth of the bitcoin network and dramatic increase in the value of bitcoin for everyone's benefit. The nChain Group of companies has grown to a team of in excess of 60 world-class scientific research, engineering and other professionals primarily based in London, United Kingdom and Vancouver, Canada.

SOURCE nChain