Like any other technology, blockchain has its disadvantages. To understand the offerings of a particular technology it is important to understand its drawbacks also.
- Excessive Energy Requirement: Mining farms with a large number of devices are used for mining. This takes up a lot of energy which is not justified by the outcome.
- Excessive Computing Requirement: Distributed ledgers are ever-growing. They can grow really large, and the storage requirement would be excessive. Even the GPU requirement is very high and recently, there was a GPU shortage because of miners buying them to mine more bitcoins.
- Security Loophole: While the consensus algorithm has been successfully managing the authenticity of the system, there is a possibility when the system may be exposed to alteration. If a user can somehow control more than 50% of the mining power, then they can make changes in the entire blockchain. This is mostly a theoretical possibility but something to ponder over.
- Scalability Problem: It may not be a problem yet but if blockchain becomes mainstream, the number of users will increase exponentially. However, there can only be so much bandwidth and the transactions would slow down making the system inefficient.
- Data Immutability: It may seem strange, but the strength of the system can be a disadvantage in some cases. Privacy issues may crop up, when personal details, medical history and other sensitive information would be permanently available even if it may not be the ideal way to present personal information in every scenario.
