- OLTP Head
Tangled up in blockchains (4)

Do I have to give up on getting any answers and wave the white flag on blockchains?
Is there anyone out there who can answer the hard questions about blockchains? If not then I'll give in and accept the fact that no reality based discussions are taking place and this will be my final blog entry in my blogchain.
There sure is a lot of hype around blockchains and as an old, and no doubt fuddy duddy, OLTP (OnLine Transaction Processing) technologist I get quite confused, as older folk often do. But if somebody, anybody, could answer the following points it would be really enlightening and a significant addition to current discussions about blockchain technology. I have looked very hard for answers and so far have failed to come up with anything convincing. In fact I have found that even some of the heavy hitters in the bitcoin/blockchain discussions are not singing from the same hymn sheet.
Please note that this blog post was partially inspired by a recent Financial Times article and any references are to that article.
Wow, “a shared global database”! Why is this considered to be so revolutionary? They've been around for years involving all kinds of specialised enabling technology such as 2PC (two phase commit).
It is said that the bitcoin blockchain can handle 7 transactions per second (yes, 7!) whereas the Transaction Processing Council's TPC-C current best benchmark results for transactions executed on a traditional relational database currently stands at over 5 million transactions per second. Hmmm.
Transaction records cannot "be altered at a later date" so cancellations are not possible. Oh well we can always go back to the 1970s and issue new contra-transactions to reverse transactions we want to cancel. Oh but hang on. Doesn't that require the active participation of the party on the other side of the transaction in a blockchain? Let's hope they've not fled to the Caribbean to spend their ill-gotten gains.
Blockchain transactions involve the transfer of ownership of digital tokens. If you can find a bunch of people to assign real financial value to these tokens, even outrageously high values, excellent. So you could let people (which people?) set up exchanges where you can sell (or buy) your tokens for actual cash. Oh, but hang on, who is going to police and regulate the exchanges?
Perhaps you could get people to agree that possession of a digital token entitles the possessor to possession of a physical object, or the terms of a contract? Well first of all see number 4, and then, unfortunately in the real world there is a massive difference between ownership and actual physical possession, and between theoretical agreement and actually acting upon an agreement. Who will be doing the regulation and enforcement? Trusted robots perhaps?