The block size of the current Bitcoin network, i.e., 1MB is not enough to store the huge number of transactions that are taking place on its network at the present time. This is causing delays in transaction validation because of the extended waiting period caused due to the formation of next network block. It causes some Bitcoin transactions a few hours before they are validated, while others may take 60 minutes or less.
The Bitcoin network doesn’t have the option to increase the block time as Satoshi Nakamoto had planned, when he decided to keep the blocks to be approximately 10 minutes apart. It will ensure that the last Block is mined by the year 2140.
The second option is to expand the block size limit, however, that too will require forking of the Bitcoin network. By forking the network, Bitcoin developers will be making the Bitcoin network capable of processing higher volume of transactions as compared to the present network. This change can prove to be a desirable one as Bitcoin is becoming widely adopted and accepted.
Increasing block size is not acceptable by all as bigger blocks would mean higher internet costs. For instance, China has varying internet bandwidth as compared to the Western world and increased block size will cost them more. It is feared by the Chinese Bitcoin mining pool that the existing internet infrastructure of their country wouldn’t be effective in handling an expanded block size. It might result in the Bitcoin network losing 60% of its mining power.
Due to this resistance, Bitcoin Core developers are looking for an alternative option that will address this challenge of Bitcoin block size. Although the block size expansion is a non-avoidable option, but an option is being put in place for less “resource intensive” Bitcoin client.
This increasing concern of the entire Bitcoin Blockchain can be effectively addressed by Blockchain pruning. At the time of writing, the Bitcoin Blockchain is about 197GB in size containing a record of all the transactions. These include those which took place when the Bitcoin first came into existence till January 2019. An increase in Block size will only result in a requirement of more storage space for the Bitcoin Blockchain.
Blockchain pruning will allow a user to validate transactions with only 550 blocks stored on their device. Although it will help with the storage problem, it won’t serve as the ultimate solution to the problem. To indulge into Blockchain pruning, the user first needs to download the entire transaction history up to that point before they start reducing the data.
With a size of 1MB per block, Blockchain pruning would allow a user to use only 550MB of their hard disk space. This will be very less than the 197GB storage space required at present, which will continue to grow.