When Bitcoin first started off, there was technically an infinite maximum block size; though, Andresen mentions that the p2p protocol limited the block size to 32 mb. Following increased media exposure for the nascent Bitcoin in the year 2010 following a Slashdot article, Satoshi himself rolled out various fixes to potential denial-of-service attacks.
Andresen's solution is as follows:
Roll out a hard fork that increases the maximum block size, and implements a rule to increase that size over time, very similar to the rule that decreases the block reward over time.
The first step of the roadmap, faster relaying times, has already been implemented by Mark Corallo earlier this year. The Bitcoin protocol needs the protocol to scale in order for it to reach its maximum potential. Andresen explained very succinctly:
I think the maximum block size must be increased for the same reason the limit of 21 million coins must NEVER be increased: because people were told that the system would scale up to handle lots of transactions, just as they were told that there will only ever be 21 million bitcoins.
Though the Bitcoin network is currently limited to seven transactions per second by way of the 1 mb block size rule, the number of transactions per second is nowhere near seven at the moment. In fact, the community has started to see increasing numbers of "offline transactions," such as those that occur when money is sent from one centralized web wallet service to another. Andresen cites Moore's Law and Nielsen's Law of Internet Bandwidth to emphasize that home computing will be able to support large transaction volumes in the future. The future of Bitcoin is always bright, and now there's a roadmap to make it bigger.
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