The Case for Banks to Use Open, Public Blockchains
Theres no doubt that blockchain technology will facilitate disruptive innovations in finance, but a world of private ledgers sounds eerily similar to a range of private Internets.
Marc Andreessen, the venture capitalist and inventor of the early Web browser Mosaic, had it right when he tweeted in December: "Big companies desperately hoping for blockchain without Bitcoin is exactly like 1994: Can't we please have online without Internet?"
In the mid-'90s, the advent of the Web led to private companies attempting to create proprietary information-sharing networks (think AOL and CompuServe). But the Internet as we know it today won out over every single private network because it was not restricted to the big players and bogged down by proprietary protocols.
Banks are at risk of making the same mistake today as they show surprising interest in private distributed ledgers, or private blockchains, rather than put their intellectual capital to use on features that enhance the appeal of public blockchains and the virtual currencies – such as bitcoin – enabled by open-source ledger systems.
If the Internet and the Web have taught us anything, it is that groundbreaking technology is often built on top of open protocols in a level playing field where anyone can innovate regardless of size and influence. Companies like Google and Facebook are possible precisely due to the open nature of the Web.
There is no doubt that the use of private distributed ledgers can provide immediate improvements to some of the creaking infrastructure underlying the financial services industry, especially in the back office of securities settlement. But the financial industry's interest in building proprietary networks is, as Andreessen put it, like having "online without Internet."
To be sure, the transmission of bitcoin, which is the primary purpose today of the public blockchain, has several limitations today that limit its use. The number of transactions per block is limited, and the bitcoin community is currently engaged in a fierce and divisive battle about how to best address scalability concerns.
The limited smart-contracts platform for bitcoin has given rise to competing public blockchains, such as Ethereum, which can theoretically run more complex contracts.
Meanwhile, the openness of a public blockchain naturally leads to concerns over whether private transactions can be carried out securely without the unwanted scrutiny of an open network. And public blockchains, in general, take significantly longer to confirm transactions than private networks.
But newer research suggests that bitcoin technology can be refined to overcome these limitations and reap the benefits of greater applicability. For example, developers are working on a cryptographic tool known as Confidential Transactions to enhance security. The tool can verify a public blockchain transaction without knowing the input amounts of the exchange, providing greater privacy than what is provided natively by bitcoin. Such a technology allows the user to settle a trade without disclosing its size, or to debit an account without revealing to the world how much money the account holds.
Privacy of public blockchains will be further enhanced through the use of "zero-knowledge proofs," a method of verification that doesn't reveal any other information except the validity of the statement. Such projects include Zcash, an open source cryptocurrency facilitating payments on a public blockchain, but where the sender, recipient and amount of a transaction are kept private. Just like how it is now possible to conduct secure e-commerce transactions over the Web, in the future it will be possible to conduct private business over a public blockchain.
Meanwhile, developers are attempting to address the scalability issues of bitcoin through so-called "sidechains," which open up new possibilities for experimentation, similar to Ethereum but backed by the more well-established bitcoin network. Rootstock is building a fully functional "Turing-complete" smart contracts platform on a bitcoin sidechain, meaning it can be used for more complex transactions than just exchanging value between two parties. The platform will allow for the creation of highly complex smart contracts, which are fundamental to applications like securities settlement.
With these bitcoin-based development efforts, the public blockchain infrastructure will become more robust and scalable for global use. It won't happen overnight, but history suggests that open technology always wins over closed-garden approaches.
Siddharth Kalla is the chief technology officer of Acupay, a technology provider in New York specializing in cross-border finance. The views expressed are his own.