These components are decentralization, scalability, and security. As a rule, projects strive to optimize all of them, but this is very hard to accomplish in practice. Why is 100% interoperability of these features such a challenge? Welcome to the article, in which we explain the technical side of this problem. 

Blockchain trilemma – discussion

Let's start by explaining what the above-mentioned functions are responsible for. 

Decentralization – means that data is stored and managed by a large number of nodes that organize the operation of the network. It provides resistance to censorship, prevents single points of failure, and loss of control, and increases transparency. In blockchain, each node has a copy of all transactions, eliminating the need for a central governing body as in traditional networks, such as the client-server model. 

Scalability – is the ability of the system to adapt to handle an increasing number of transactions and users. In blockchain, the goal is to enable as many transactions as possible in a short period. There are various approaches to increasing scalability through, for example, sidechain and secondary layer technologies, block augmentation, various sharding consensus algorithms, or zero-knowledge proof solutions.

Security – refers to the network's resilience to attacks or abuse, such as double-spending, 51% attacks, or data forgery. Although blockchain is one of the most trustworthy technologies, there are various risks that need to be mitigated as much as possible so that users can enjoy safe use of the network.

Scenarios for blockchain trilemma

Let's look at the practical side of the trilemma, in which priority is placed on two of the three aspects of the network's operation.

Decentralization and security at the cost of scalability – the requirement is to incur significant computational expenses, as each node must perform complex cryptographic calculations and store the increasing size of the blockchain. Scalability loses out, as storing the full transaction history becomes increasingly expensive as the network grows.

Security and scalability at the cost of decentralization – a network may choose to have fewer nodes processing and storing the full transaction history, but this naturally reduces the level of decentralization, reducing the distribution of computing power. 

Decentralization and scalability at the cost of security – in this scenario, the network may, for example, opt for less rigorous consensus algorithms requiring lower computing power, but these may be easier to exploit by actors willing to act against the system. 

Will the blockchain trilemma ever be solved?

Emerging projects and existing networks seek to optimize and balance the three components mentioned above. They often offer innovative technological solutions, such as rollups and sharding. Blockchain is a technology that is constantly evolving. Over the years, we can expect a variety of approaches to solving this problem - finding a one-size-fits-all answer is unlikely to happen quickly. It's worth keeping an eye on this aspect of blockchain development to remain as informed a blockchain user as possible.