Gavin: I cannot support the central planning vision of Bitcoin

A few months ago, Paul Sztorc published a blog post in which he raised two very good questions:

1. “Why do you think we have a block size cap?”

2. “What has changed between July 15, 2010, when the block size cap was introduced, and today, that prompted us to make that change in constraints?”

For me personally, the answer is simple. First, the cap was increased to prevent 'poison block' network denial of service (DoS) attacks. We worry about DoS attacks if the cost to the attacker is low. 'Amplification' attacks are bad, where the attacker sends only a small amount of information and causes congestion on the network or causes a lot of CPU processing to be wasted.

Second, a lot of key things have changed since Satoshi made this restriction.

Today, the network is much more expensive to attack. I have a spreadsheet of all bitcoinmarket.com (the oldest bitcoin exchange) transactions. On July 15th, about 11,000 BTC were traded at an average price of 3 cents.

At that time, the block reward was still 50 BTC, so miners could exchange the reward for one block for about $1.5. According to a rough estimate, the cost for an attacker to generate a "poison block" to disrupt the network is about $1 to $2. Many people are willing to spend $1 to $2 for "fun". They like to make trouble and are willing to spend a lot of time and money to cause some trouble.

Today, the Bitcoin block reward has become 25 BTC, and its unit price has exceeded $400, so the reward for a miner for one block is more than $10,000. If an attacker wants to generate a "poison block", he needs to spend a similar amount of money.

Additionally, a few other things have changed since July 2010, and we know that it is possible for an attacker to produce blocks that are very expensive to verify (even with the 1MB block limit set by Satoshi five years ago). This was mentioned in a report by Sergio Demian Lerner back in 2013.

The fact that no one is producing expensive blocks to attack the network is a good proof that such attacks are unprofitable... but it is a good idea to completely eliminate the possibility of "poison block" attacks. BIP 109 eliminates this attack in a simple way and makes it safe for blocks to increase their upper limit.

So we know how to safely raise the limit. In 2010, the Bitcoin network was confirming a few hundred transactions per day, and now it's confirming hundreds of thousands of transactions per day. More and more users are reporting trouble with transaction confirmations, and even the smartest transaction fee estimation code can't stop transaction confirmations from becoming increasingly unreliable.

See Paul's blog post for other people's answers to the question "Why do we have a blocksize cap?"

In my opinion, the reason people are using this block size cap is something that has never happened with Bitcoin, and it is intended to influence how people use the Bitcoin blockchain and force some uses off the blockchain.

They also have good reasons to do so, believing that their vision for the future of Bitcoin is better than (safely) raising or removing the cap.

I cannot support this top-down, center-planning type of vision.

Original article: http://gavinandresen.ninja/One-Dollar-Lulz
By GAVIN ANDRESEN
Compilation: Overnight porridge
Source (translation): Babbitt Information (http://www.8btc.com/centrally-planned-vision)