Bitcoin SV- SATOSHI VISION (BSV) Bitcoin Cash Hard Fork
“The nature of Bitcoin is such that once version 0.1 was released, the core design was set in stone for the rest of its lifetime.”
– Satoshi Nakamoto
What is Bitcoin Cash?
Bitcoin Cash is an experimental digital currency that enables instant payments to anyone, anywhere in the world. It uses peer-to-peer technology to operate with no central authority: managing transactions and issuing money are carried out collectively by the network. Bitcoin Cash is a descendant of Bitcoin. It became a separate currency from the version supported by Bitcoin Core when the two split on August 1, 2017. Bitcoin Cash and the Bitcoin Core version of Bitcoin share the same transaction history up until the split.
What is Bitcoin SV?
Bitcoin Satoshi Vision (SV) is the name of open-source software which enables the use of Bitcoin Cash.
The source code was originally based on the Bitcoin ABC software project.
Bitcoin SV is a full-node implementation for Bitcoin Cash (BCH) and will maintain the vision of Bitcoin set out by Satoshi Nakamoto’s white paper in 2008: Bitcoin: A Peer-to-Peer Electronic Cash System
Reflecting its mission to fulfil the vision of Bitcoin, the project name represents the “Satoshi Vision” or SV. Created at the request of leading BCH mining enterprise CoinGeek and other miners, Bitcoin SV is intended to provide a clear BCH implementation choice for miners and allow businesses to build applications and websites on it reliably.
Bitcoin SV restores the original vision to ignite the future of Bitcoin:
- Bitcoin Cash can replace every payment system in the world with a better user experience, a cheaper merchant cost, and a safer level of security.
- Businesses can trust the Bitcoin Cash brand to provide the stability and scale they need to commit investment and resources to use the BCH blockchain.
Four fundamental pillars form the basis of Bitcoin SV’s roadmap to create the one blockchain for the world: stability, scalability, security, and safe instant transactions (a.k.a 0-confirmation).
“The existing Visa credit card network processes about 15 million Internet purchases per day worldwide. Bitcoin can already scale much larger than that with existing hardware for a fraction of the cost. It never really hits a scale ceiling.” – Satoshi Nakamoto (April 2009)
1 – Stability
Businesses, especially the biggest enterprises, require stability before they will operate on a technology platform. Repeated, unnecessary, and unproven changes to the Bitcoin protocol can be detrimental to the economic incentive structure and security of the blockchain. They can also cause significant uncertainties for large scale businesses that need to plan years in advance and commit significant resources before deciding to build applications and projects on Bitcoin Cash.
The Bitcoin SV vision is to provide assured stability with only a limited and well known set of changes planned to restore the Bitcoin protocol to its original design, and enable innovation to occur on top of a stable base protocol.
Part of this is restoring the Satoshi op_codes to enable businesses and development teams around the world to create the many solutions possible on the BCH blockchain, such as smart contracts, tokenisation, atomic swaps, and many more.
2 – Scalability
In order for Bitcoin Cash to truly act as a global money platform, it is necessary to demonstrate that the platform is ready to process transaction volume at the required scale. The Bitcoin SV roadmap is primarily focussed on delivering capacity increases, through bigger default or miner configurable block sizes and performance improvements. Out of the nine test environments in use by the project, the SV Gigablock Testnet (SV-GBTN) is specifically dedicated to identifying bottlenecks and performance measurement of proposed changes. The SV-GBTN is running on a continuous cycle of performance tests and the results of those are for public consumption so that miners and other industry participants will be able to make informed scaling decisions.
By enabling massive scaling, Bitcoin SV will pave the way for the BCH blockchain to support significantly higher transaction volumes and more transaction fees for miners. This is important for miners to maintain profitability as the block reward will halve again in the year 2020 (reducing from 12 BCH to 6.25 BCH for each block), and halve again in later years.
Massive scaling is also important to convince enterprises to use BCH for their blockchain applications – which will require big blocks and large throughput capacity.
3 – Security
Bitcoin Cash will be a global currency. To enable such a future, we need to be prepared to ensure a level of security commensurate with a global money system. To do this, the Bitcoin SV project has focused on rigorous Quality Assurance for mining node software.
This is achieved by implementing a rigid set of test phases with full traceability throughout the test pipeline, to assure users that changes pass through a formal and rigorous validation process before they are accepted. In this respect, Bitcoin SV aspires to levels of Quality Assurance exemplified by mission critical industries such as aerospace, medicine and national security.
First, the team will use best practice change management processes and engage external QA expertise from other security-sensitive industries to monitor and audit its QA processes.
Second, the project will engage the services of an industry-leading blockchain security audit firm.
Third, the project will offer a lucrative bug bounty program matching the likes of Google and Microsoft to motivate and mobilize security researchers around the world to find and responsibly report security vulnerabilities. The team has engaged expert service providers in the field to develop an industry best practice “Responsible Disclosure Program.”
4 – Safe instant transactions (a.k.a. 0-conf)
Instant transactions are key to unlocking the brick and mortar merchant market for Bitcoin Cash payments. Security improvements can be made to better secure instant transactions for the future, and the Bitcoin SV roadmap treats safe instant transactions as a key priority.
Security is core to our values, and we value the input of security researchers acting in good faith to help us maintain high standards of security and privacy for our users and the Bitcoin Cash blockchain. This includes encouraging responsible vulnerability research and disclosure. This policy sets out our definition of good faith in the context of finding and reporting vulnerabilities, as well as what you can expect from us in return.
When working with us according to this policy, you can expect us to:
- Extend Safe Harbor for your vulnerability research that is related to this policy;
- Work with you to understand and validate your report, including an initial response to the report within 72 hours of submission;
- Work to remediate discovered vulnerabilities in a timely manner; and
- Recognize your contribution to improving our security if you are the first to report a unique vulnerability, and your report triggers a code or configuration change.
When conducting vulnerability research according to this policy, we consider this research to be:
- Authorized in accordance with the Computer Fraud and Abuse Act (CFAA) (and/or similar state laws), and we will not initiate or support legal action against you for accidental, good faith violations of this policy;
- Exempt from the Digital Millennium Copyright Act (DMCA), and we will not bring a claim against you for circumvention of technology controls;
- Exempt from restrictions in our Terms & Conditions that would interfere with conducting security research, and we waive those restrictions on a limited basis for work done under this policy;
- Lawful, helpful to the overall security of the Internet, and conducted in good faith.
You are expected, as always, to comply with all applicable laws.
If at any time you have concerns or are uncertain whether your security research is consistent with this policy, please submit a report through one of our Official Channels before going any further.
To encourage vulnerability research and to avoid any confusion between good-faith research and malicious attack, we ask that you:
- Play by the rules. This includes following this policy, as well as any other relevant agreements. If there is any inconsistency between this policy and any other relevant terms, the terms of this policy will prevail.
- Report any vulnerability you’ve discovered promptly.
- Avoid violating the privacy of others, disrupting our systems, destroying data, and/or harming user experience.
- Use only the Official Channels to discuss vulnerability information with us.
- Keep the details of any discovered vulnerabilities confidential until they are fixed, according to the Disclosure Terms in this policy.
- Perform testing only on in-scope systems, and respect systems and activities which are out-of-scope.
- If a vulnerability provides unintended access to data: Limit the amount of data you access to the minimum required for effectively demonstrating a Proof of Concept; and cease testing and submit a report immediately if you encounter any user data during testing, such as Personally Identifiable Information (PII), or proprietary information.
- You should only interact with test accounts you own or with explicit permission from the account holder.
- Do not engage in extortion.
To help us receive vulnerability submissions we use the following official reporting channel:
- email: [email protected]
If you think you’ve found a vulnerability, please include the following details with your report and be as descriptive as possible:
- The location and nature of the vulnerability,
- A detailed description of the steps required to reproduce the vulnerability (screenshots, compressed screen recordings, and proof-of-concept scripts are all helpful), and
- Your name/handle and a link for recognition.
Please encrypt all information that you send to us using our PGP key. The fingerprint for this key is E8EB 970A 1C60 7DF0 822E 1388 F969 76FD 7A20 AB62.
We may modify the terms of this program or terminate this program at any time. We won’t apply any changes we make to these program terms retroactively.
A ‘bounty’ or reward may be payable for the responsible disclosure of vulnerabilities in accordance with our policy and ground rules, and provided that the BitcoinSV security team is one of the original recipients of the disclosure.
The final amount is always chosen at the discretion of the reward panel, but the general guidelines below provides examples of the maximum rewards that may be payable based on the severity of the vulnerability that has been found. It should be noted that only vulnerabilities that are economically feasible will be considered e.g. 51% attacks on the network will be considered economically unviable.
*All rewards will be paid out in Bitcoin Cash from CoinGeek Mining’s open source budget.
Our bug bounty program focuses on the code base for Bitcoin SV and spans end-to-end: from soundness of protocols (such as the blockchain consensus model, the wire and p2p protocols, proof of work, etc.), protocol implementation and compliance to network security and consensus integrity. Classical client security as well as security of cryptographic primitives are also part of the program.
Scope is limited to code contained in specified branches of the repository located at: https://github.com/bitcoin-sv. Branches in and out of scope are specified by the branch name:
Branches in scope:
- master branch
- most recently updated branch with prefix: rc-*
- branches prefixed with: review-*
Branches out of scope:
- branches prefixed with: dev-*, exp-* or research-*
- all other branches not specified as in scope
- Findings from physical testing such as office access (e.g. open doors, tailgating)
- Findings derived primarily from social engineering (e.g. phishing, vishing)
- Findings from applications or systems not listed in the ‘Scope’ section
- Findings that have already been reported
- UI bugs and spelling mistakes on this or any associated website
- Network level Denial of Service (DoS/DDoS) vulnerabilities
Please note, we do not want to receive any sensitive data during any disclosure, such as personally identifiable information (PII) or any data associated with private/public keys.
If in any doubt, send an email to [email protected]
The following key should be used to communicate sensitive information via email:
Fingerprint: E8EB 970A 1C60 7DF0 822E 1388 F969 76FD 7A20 AB62
The Bitcoin SV project assures its commitment to stringent quality with several measures.
the team has implemented best practice change management processes, and
has engaged external QA expertise from security-sensitive industries to
monitor and audit these processes. Furthermore, the Bitcoin SV project
has commissioned a dedicated QA team consisting of a QA manager and
three dedicated QA Engineers responsible for the development and
maintenance of test environments as well as performing, documenting and
approving all changes.
Second, the project has engaged the
services of an industry-leading blockchain security audit firm. This
outside team will serve two purposes:
1. Complete a full security
audit of the Bitcoin SV code base. This audit will cover not only the
code itself but also development practices and processes to assist in
building the most robust node development team in the industry.
2. Provide ongoing review and threat analysis of all code changes as and when they are submitted as candidates.
the Bitcoin SV project will offer a generous bug bounty program (funded
by CoinGeek) to motivate and mobilize security researchers around the
world to find and report security vulnerabilities. With input from
expert service providers in the field, the Bitcoin SV team is developing
an industry best practice “Responsible Disclosure Program.” Bounties
are dependent on bug criticality with the highest severity attracting a
bounty of USD $100,000 (payable in Bitcoin Cash).
The Bitcoin SV project begins by restoring what was the original Bitcoin
protocol. We embrace the fact that Satoshi used script as a predicate
to enable functionalities that go hand in hand, and beyond the function
of cash. Re-enabled Satoshi op_codes provide the methods needed for
smart contracts, tokenisation and other advanced technical functions to
be done on BCH. The original protocol has what Bitcoin needs to thrive,
and should be allowed to flourish without constant changes.
restored, the Satoshi protocol needs to remain stable. The protocol
should be locked down except for any critical security fixes that might
be required. This stability will give enterprises of the world
confidence to build their applications and projects on top of BCH. Just
like the Internet lives on a protocol that has changed very little since
its beginning and allows businesses to reliably plan long term projects
on the platform, the Bitcoin Cash blockchain will provide the same
The next key pillar is to ignite massive scalability
on the BCH blockchain according to future market needs, rather than just
viewing current payment transaction volume. Potential demand is a
function of supply (among other things) and we intend to provide the
capacity for BCH to act as the foundation for the entire financial world
and many other industries. Major enterprises want to know the
blockchain has sufficient scale for their projects before they commit
significant resources and time to build on BCH. Miners needs massive
scaling to earn more money from transaction fees in order to offset the
block reward halving over time. Therefore, block-size limits need to be
many magnitudes bigger than current throughput demand and ultimately
allow for unlimited growth.
Along the way, security is always
important to Bitcoin SV’s roadmap. By making sure the necessary
optimisations, testing and quality assurance steps are in place, we
allow nodes to mine big blocks and scale to global market demands in a
safe and reliable manner.
An excellent payment experience is also
needed. The Bitcoin SV project will work on both measurement and
improvement of the safety of 0-conf transactions, fast transaction
propagation, and miner-configurable fee policies.
The Bitcoin SV team has been assembled with a view to realizing industry
best practices, in order to deliver and maintain a full-node
implementation with an unprecedented commitment to quality assurance and
The Lead Developer is Daniel Connolly, who joined
nChain after 20 years in enterprise systems and held senior IT positions
with various United Nations agencies. Daniel contributed anonymously to
Bitcoin for several years, has contributed to the Electron Cash
project, and is a primary contributor to the BitcoinJ-Cash project.
Shadders will act as Technical Director, providing project oversight
and liaison with sponsors and industry participants. Steve began
contributing to Bitcoin in 2011, authoring one of the first open-source
mining-pool engines and was one of the earliest contributors to
In addition, the Bitcoin SV team has a pool of five
full time C++ developers with over 95 collective years of development
experience. An external partner is providing the services of two
additional senior C++ developers.
The QA team consists of a QA
manager and three dedicated QA Engineers responsible for the development
and maintenance of test environments as well as performing,
documenting, and approving all changes.
Additional support and management services are provided by nChain’s Project Management office and Business Services unit.
Bitcoin SV Mines 64 MB Block on Bitcoin Cash, Largest Ever on a Public Blockchain
20 November 2018 – Bitcoin SV, the new full node implementation for Bitcoin Cash (BCH) mined a 64MB block, the world’s largest ever on a public blockchain. The huge block was mined by CoinGeek Mining, during an on-going Professional Stress Test of the BCH network. Just one hour before, a 38MB block was mined, also using the Bitcoin SV implementation, by SVPool, a personal initiative of nChain’s Chief Scientist Dr. Craig Wright. That 38MB block held the record for largest block mined on a public blockchain until the 64 MB block dwarfed it.
The BCH Professional Stress Test is designed to test the BCH blockchain’s throughput capacity. The 64 MB block came at block height 557335 and the 38 MB block came at block height 557333 on the BCH network. Powered by Play.BCH.cash and organized independently of any BCH full node implementation team, the testing group also ran November 10 pre-test, in which Bitcoin SV mined five 32 MB blocks, which were then the largest ever blocks mined on a public blockchain. Bitcoin SV thus continues to demonstrate its record-setting capabilities, with larger blocks now mined of 64 and 38 MB.
Bitcoin SV is currently in the midst of a “hash war” with Bitcoin ABC to be the leading BCH implementation, with miner votes that began with the November 15 BCH network upgrade. Although Bitcoin ABC has taken an early lead, its support relies heavily upon “rented” hash borrowed by its backers (Bitcoin.com and Bitmain Technologies) from miners on the rival Bitcoin Core (BTC) network ; in contrast, the hash backing Bitcoin SV is sustained Proof of Work from miners committed to support the BCH network on an on-going basis and which should count as legitimate votes for the “Nakamoto consensus” that determines protocol rules according to the original Bitcoin white paper.
The Professional Stress Test results confirmed that Bitcoin SV is correct about its scaling roadmap: the BCH blockchain can handle much larger blocks and quickly scale for big enterprise use. Named for the “Satoshi Vision” of Bitcoin’s creator Satoshi Nakamoto, Bitcoin SV intends to restore the original Bitcoin protocol, keep it stable, and allow it to massively scale to a global network used by billions of people. For the recent November 15 protocol upgrade, Bitcoin SV lifted its default maximum block size to 128MB from the prior 32MB; that opened the door to the record-breaking 64MB and 38MB blocks. In contrast, Bitcoin ABC has kept its default block cap at 32MB, and is taking a slower scaling approach.
Bitcoin SV’s lead developer Daniel Connolly remarks:
“This is the next in a series of record-breaking blocks mined by Bitcoin SV. I believe we will see even bigger blocks reaching closer to our new 128MB default limit, especially when we eventually lift the default block cap altogether so miners can configure their own limits. The Satoshi Vision requires massive blocks, so businesses can do more complex transaction types and miners can earn more transaction fees.”
Bitcoin SV Technical Director Steve Shadders adds:
“For Bitcoin to achieve the Satoshi Vision, major businesses need confidence to build on a blockchain that has block capacity to support enterprise-level applications and projects, not just transactions between individual users. By locking down the protocol we can focus all our attention on scaling solutions that are needed to demonstrate that Bitcoin is ready for serious investment. That is what
distinguishes Bitcoin SV from the other implementations, and is exactly why miners and businesses should choose Bitcoin SV over Bitcoin ABC to unlock Bitcoin’s massive potential.”
The Bitcoin SV project was created at the request of and sponsored by Antiguan-based CoinGeek Mining, with development work initiated by nChain. The project is owned by the Antiguan-based bComm Association on behalf of the global BCH community, and the Bitcoin SV code is made available under the open source MIT license. For more information about Bitcoin SV, visit www.bitcoinsv.io.
User guide to managing BCH coin splitting
On November 15, 2018, the Bitcoin Cash (BCH( blockchain underwent a contentious hard fork with two competing rule sets: (1) one path championed by Bitcoin ABC that began a path to radically alter the original Bitcoin protocol designed by Satoshi Nakamoto; and (2) one championed by Bitcoin SV (Satoshi Vision) which sought to preserve the original Satoshi protocol and return Bitcoin closer to its original state. In subsequent days, Bitcoin ABC unilaterally introduced further consensus changes that introduced vulnerabilities to the BCH network, and abandoned the fundamental principle of Proof of Work as the security model of Bitcoin. The end result of these events is that Bitcoin Cash has now split into two persistent chains: Bitcoin SV (ticker: BSV) and Bitcoin Cash (ticker: BCH). Bitcoin SV no longer recognises BCH as Bitcoin. However, users who held BCH prior to the hard fork on November 15,, 2018 now have coins on both chains. For the stability of the markets, such users must be given effective means to deal with those coins safely.
Given that neither side of the hard fork introduced transaction repay protection, it is now possible that when sending a transaction of BSV, the same transaction can be validly replayed on BCH. This may not be the desired result and can cause confusion to users. In order to prevent this behaviour, the coins must somehow be separated. There are several techniques for doing so with various levels of complexity.
If you have no need to transact your coins in the near future, the best option is to wait and conduct no transactions now. A consensus level fix to this problem will be implemented in due course. As Bitcoin ABC has consistently refused to do so either unilaterally or mutually with Bitcoin SV, the Bitcoin SV project team has made the decision to do so itself in order to promote stability for users and economic participants on both blockchains. A consensus level fix is being developed that will prevent this being issue for users of either chain. However, to minimise disruption, it must be widely supported by wallets, exchanges and other economic actors in the Bitcoin ecosystem. We will announce a timeline for this fix once an adequate level of ecosystem readiness is apparent. This is unlikely to be before the New Year 2019. However, once implemented, there will be no further need for user action other than a wallet upgrade.
If you wish to transact with your coins before this ecosystem wide fix is implemented, you will need to split your current BCH coins. There are several mechanisms to do. However, it is first recommended that you create a new wallet for each chain to hold your separated coins. Wallets known to support BSV are listed on the BSV implementation website: https://bitcoinsv.io/services/
Several exchanges will perform the coin-splitting function for you. However, in selecting an exchange, it is important to first check that it actually does offer this service. Some exchanges have stated that if unsplit coins are sent to them, they make no guarantees that you will get access to both coins. Once deposited, you can either sell one or both coins or simply withdraw them into separate wallets. Exchanges that have openly stated they support splitting of BCH coins sent to their wallets include:
Caution: Do not assume that because an exchange has trading pairs for BSV (or BCH-SV) and BCH that it is guaranteed to support coin splitting. It is recommended you contact the exchange to confirm this before sending any coins, or send a very small amount first as a test. We will update the above exchange list as we confirm support for coin splitting behaviour with more exchanges.
Coin splitting tools
There are several coin splitting tools currently available. However, we cannot recommend any of them at this stage. Running coin splitting software gives that software access to your coins and without a high level of assurance that the software is not malicious, there is always the risk of coin theft.
The Bitcoin SV team is developing its own endorsed coin-splitting tool, which will be released and announced on https://bitcoinsv.io/news/ as soon as possible. Additionally we will be reviewing existing tools and providing a list those we consider safe.
Further methods will be available soon
In addition to the above, the Bitcoin SV team will be providing additional well-tested mechanisms in the near future, including a wallet customised to automatically coin split. These tools will also be announced on https://bitcoinsv.io/news/ as soon as they are ready. Meanwhile, we urge caution as the uncertain environment creates many opportunities for fraudulent services to take advantage of user confusion. The official Bitcoin SV website will not recommend any service or software for this purpose unless we have thoroughly tested and reviewed it ourselves. We will also provide best practice procedures for using any coin-splitting services or software.