Bitcoin Block Confirmation Reaches 2009 Levels – Is Security a Concern?

Bitcoin is in an uncomfortable position. Statistics from Glassnode reveal that, given the mass exodus of China’s miners, the current BTC mining process is having an adverse effect on transaction speeds. On June 28th, the average block confirmation time was 1,958 seconds (or 32.6 minutes)– the longest time it has been since 2009, the year Bitcoin was created.

For context, it usually takes 10 minutes for a block confirmation. Let’s look at why this happened, and whether such behavior could leave the Bitcoin network vulnerable in terms of security.  

Bitcoin Mining Feels the Impact of China’s Ban

The reason Bitcoin transactions took so long on June 28th was because miners are currently in the process of exiting China, as they were forced to leave the country. This has left miners unable to engage with the Bitcoin blockchain as they try to re-locate and find suitable places to continue their work. 

As a result, there are fewer active miners on the network, which has led to longer transactions as there are fewer people who can readily process blocks on the chain. It would appear that June 28th saw the worst of it, with block confirmation times peaking at 32.6 minutes. To put this into perspective, Bitcoin requires six block confirmations before a transaction is treated as genuine and fully verified, meaning that on this day a full transaction took 192 minutes (or 3.2 hours). 

For context, the Bitcoin network aims to have blocks confirmed within 10 minutes (although this target is not always reached). The block confirmation times did however drop the next day, moving to a much more reasonable 13-15 minutes. 

Such long confirmation times were previously thought of as a thing of the past. It was not since 2009 when confirmations were taking that long, which was incidentally the year of Bitcoin’s birth. At that time, Bitcoin had no established price, and Satoshi was still an active member of the community, mining from their own CPU. 

Join our Telegram group and stay connected to all things crypto, DeFi, and finance.

Is Bitcoin’s Drop in Mining Difficulty a Security Concern?

A fair question to ask would be whether this leaves Bitcoin open to attacks or other malicious behavior. Hacks have been taking place on other blockchains such as the Binance Smart Chain this year, and on smaller DeFi projects throughout last year. While these attacks targeted protocols built on top of blockchains and not the actual blockchains themselves, the situation still warrants some concern over Bitcoin’s security.

For starters, understand that Bitcoin miners are a huge part of the network. Not only are they needed to validate and facilitate all transactions, but they play a major role in maintaining the security of the blockchain.

Bitcoin works best when it has more miners. This is evident in the recent drop in miners which triggered the rise in transaction times. More miners mean that the network runs faster and swifter. 

It is reasonable to fear that if there are fewer miners, or at least fewer miners with an enormous amount of resources (electricity and hardware) dedicated to securing the Bitcoin blockchain, then the network might be more at risk. However, it is not as simple as this. More miners are important, but what is more important is the distribution of miners.

Bitcoin is strongest when it is most decentralized, and this is because a high concentration of miners in one location, or large amounts of miners who all pool their resources together (rather than work independently) which can make the network susceptible to 51% attacks.

A 51% attack is where over 50% of a blockchain is controlled by one centralized body. It is where the majority of miners (or validators, if we’re talking about certain proof-of-stake consensus mechanisms), work together to gain control of the blockchain and then manipulate it by making their own transactions. 

A paper from the University of the West of Scotland goes into explicit detail about how these attacks function. In theory, it seems that it would be easier for a 51% attack to occur if there are fewer active miners, but in truth, the distribution of miners is more important.

Despite the fact that there were more active miners before China’s crackdown, it also meant that there were more miners in one specific location, making it possible for China to potentially disrupt the blockchain if it wanted to. But now that those miners are spreading into other countries, this reduces the risk of a coordinated attack because of how they are distributed, therefore increasing Bitcoin’s decentralized nature.

In essence, the reduction in miners on June 28th did not cause too much of a security risk, because while there were fewer miners than before, more miners were located across the world. It is unlikely that we will see transaction times reach 30+ minutes again for a while, as most miners have either successfully relocated, or are in the process of doing so as we speak, so this behavior is not expected to get repeated.

Do you think we should be concerned about the future of Bitcoin’s security? Let us know in the comments!