Overview of the Internet computer's consensus protocol

March 7, 2024

Overview of the Internet computer's consensus protocol

The unique idea behind ICP is to invent a new type of decentralised internet and global computing system in which independent data centres around the world can come together to collaborate and create an alternative to the cloud services. This makes ICP stand out as a platform that is laying the foundation for revolutionising the landscape of the internet.


A very key function of this innovation lies in its “consensus mechanism”, a fundamental component that drives the decentralized nature of the Internet Computer and holds the key to it potentially reinventing Web 3.0.


The consensus mechanism plays a decisive role in ensuring the integrity and security of the network. Unlike traditional centralized systems where decision-making authority is cornered in the hands of a few entities, the Internet Computer leverages a decentralized consensus mechanism to achieve trust and consensus among its participants.


Summary of how the consensus mechanism works on ICP;


The Internet Computer employs a novel consensus mechanism known as the Threshold Relay Consensus (TRC). This mechanism is designed to enable the network to achieve both security and scalability without sacrificing decentralization. The ICP achieves these properties through a consensus protocol where different machines, or replicas, must agree on inputs and order to maintain a coherent state.


In simple terms, TRC works by distributing the task of reaching consensus among a large number of nodes in the network. Rather than relying on a single entity or a small group of validators to confirm transactions,


Any secure consensus protocol should guarantee these properties:

  • Safety: meaning that, if two honest replicas think that they agree on the blockchain up to a certain point, then they should keep the same view of the blockchain up to that point.
  • Liveness: meaning that the blockchain keeps progressing and keeps agreeing on more and more blocks continuously.


ICP’s consensus protocol is designed to be

  • simple,
  • robust (performance degrades gracefully when some replicas are crashed or malicious), and
  • optimistically responsive (when certain optimistic conditions are met, the protocol may proceed at the pace of the actual network delay, rather than some worst-case upper bound on the network delay).


As we explore the Web 3.0 era, the Internet Computer's consensus mechanism holds the promise of empowering users and developers with a more open, secure, and inclusive Internet. By embracing decentralisation and blockchain innovation, the Internet Computer paves the way for a future where digital sovereignty is restored to individuals, creativity flourishes without constraints, and most importantly trust is inherent in the fabric of the Internet.