For all the froth and hype about blockchain, you’d think it was going to bring about world peace, and simultaneously solve every problem known to mankind. There’s probably been more tosh written about it over the past year or so than all that previous guff about “big data”. Quite frankly, I’m disappointed blockchain hasn’t defeated ISIL single-handed and rebuilt the Seven Wonders of the Ancient World by now. Come on blockchain, what are you waiting for?!
Blockchain is being misunderstood and over-hyped to the point where any rational discussion of where it might be useful – and where it might not be – has become buried beneath a sea of self-serving hyperbole. It may do one or two things well – such as distributed ledgers for financial or supply-chain transactions – but it’s also socially and technologically ill-suited in many other contexts. Yet most of the people writing about its potential uses seem to have little understanding either of the technology or the practical limitations on its use outside of some well-defined and well-bounded scenarios.
For those who’ve slumbered through the tsunami of hype, a blockchain is essentially a public ledger of all transactions that have ever been executed. It provides proof of all the transactions on a network and a full history of transactions in the order that they occurred. Transactions are entered chronologically in a blockchain and the blockchain database is shared by all nodes participating in a system so that no single node can ever be in the position of falsifying or tampering with it.
The blockchain contains records of every transaction ever executed. It can be used to ensure that transactions have happened and cannot be tampered with, yet it can also potentially retain a degree of anonymity – which is why it has provoked such interest with Bitcoin, the digital currency, since it enables secure financial transactions to take place without necessarily revealing who is involved in those transactions and without needing a single, central authority to oversee the system.
These characteristics – proof that a transaction, such as a purchase or payment of tax, has happened, combined with potential anonymity – make it a candidate technology to be considered for use in various scenarios. However, the ability to maintain anonymity may require better design than that currently used in the Bitcoin network, as this paper (PDF) points out, and its vulnerability to concerted manipulation by an adversary with sufficient computational power remain a concern. This piece is also interesting about its limitations and (possible) future direction.
So let’s take just some of the problematic examples where it’s been suggested that blockchain technology will offer a miracle solution.
First up, registers of births and deaths. Well, who could argue with the idea of an immutable public register of births and deaths? Along with taxes, there’s nothing more certain than births and deaths is there? Exactly the sort of area where absolute trust and assurance is needed.
Well – possibly. If that is you ignore some inconvenient truths. If that is you don’t understand some of the essential edge cases that need to be handled in the imperfect and often flawed world in which we live. There are various examples where an immutable public record could turn out to be a very bad idea.
Let’s take the example of someone entering a witness protection programme. The usual need is to provision these brave souls with an entirely new, but believable, identity. One with a credible historic footprint.
Hmm. But how would you do manage to do that if there is no ability to insert a back-dated record into the public, immutable, and massively loved and trusted register built on blockchain technology?
Well, possibly you could randomly continually seed a lot of fake births into the immutable public register just in case they might come in useful one day. But then that rather defeats the point of an authoritative public record which can be trusted. It also runs the danger that such fake birth records would be used for other, less altruistic purposes by anyone else who becomes aware of their existence.
Possibly you could put a façade in front of the register, masking the real one and enabling the insertion of new records from a side-chained system so that the end result is a composite of the original core register and the side register containing birth and death records required for other purposes, such as witness protection.
Well, not surprisingly this approach is not without its drawbacks, including that the “trusted register” itself is not what is actually directly available, rather undermining its supposed immutability and trust. And the second, side system becomes an interesting risk entity in itself – a very attractive target if you either want to track fake records being created, or if you want to bribe someone to create records for more nefarious purposes.
Ah well, you may think, perhaps ideas like blockchain aren’t best suited in this type of environment. But surely they can be used elsewhere, such as the land registry. After all, that needs to be reliable and we need to know it hasn’t been tampered with: it’s the authoritative record of all land ownership after all, isn’t it?
Well – perhaps. But let’s continue with our previous example, the poor old witness in the protection programme. Having (somehow) overcome the problems of creating an entirely new identity with a credible historic footprint and somehow reverse engineered it into the “trusted” immutable (cough) public record, the witness now needs to be given a new place to live. Fine. So their new name is entered on the immutable, authoritative land registry as the proud owner of a new home.
Hmm. This doesn’t seem like such a great idea. Firstly, a new name has now appeared on the register for the first time around the same time that their previous persona disappeared. Someone might find it interesting to correlate the disappearances of witnesses and the appearances of new identities around certain dates and court cases, particularly of people who have never previously appeared on the register. Secondly, the witness with their shiny new identity is meant to have a credible back history: yet there would be no scope or flexibility to amend the land registry to make it look as if that person had been resident at their new home for far longer, or to make it appear as if they had moved from somewhere else – all useful camouflage when helping construct a credible back-story around a newly established identity, and to obfuscate simplistic correlation vulnerabilities.
So here we encounter the same problems again: how would a credible historic social footprint be created for those who need one if blockchain-powered, public immutable registers become the norm? And yes, of course those in witness protection programmes may be an edge case, but similar problems arise in other areas, such as battered spouses, at risk children, undercover law enforcement and agency officers. Anyone for whom there is a legitimate need to provision a new identity and historic, credible social footprint.
All of these examples can of course be airily dismissed as edge cases, as indeed they are. But it’s these very edge cases that characterise a unique problem space in the public sector. It’s these hard, life-impacting, very human issues that the public sector has to worry about. This is why the public sector cannot simply let itself be swept along by every fad and fashion that blows through the IT industry without objectively considering the implications. Copying what others are doing, riding along on the hype-wave and joining in the chorus of “Me too!”, has never been a viable strategy – least of all when it concerns matters of potential life or death.
These are complex problems, ones that are not going to be resolved by government playing mini-me to the hype merchants and ill-informed commentators swept up in their own make-believe worlds. Government needs to cut through the hype and assess both the technical and social limitations of any new technology such as blockchain and decide very carefully if and where it may play a useful role. Any less strategic approach is likely to produce unforeseen and undesirable outcomes, including the potential breakdown of trust in some of our most essential public services.