Not a day goes by in the blockchain space in which we don’t hear complains about the scalability and performance issues with first generation blockchain platforms such as Ethereum. Providing alternatives to Ethereum has become like its own market within the blockchain ecosystem with solutions such as EOS, Stellar or Cardano trying to become the next generation blockchain platforms. Recently, I started deep diving into the ZILLIQA project and have been blown away by their technological depth and mathematical rigor. Without getting into the predictions game, it is safe to assume that ZILLIQA is one of the projects that can play a prominent role in the next generation of blockchain platforms.
ZILLIQA was initially incubated by the Singapore-based technology firm Anquan but quickly become a standalone entity after gaining notoriety in the space. From the first glance, ZILLIQA comes across as a sophisticated platform maybe because the project its building upon 2+ years of research in blockchain scalability techniques. The main idea behind ZILLIQA is to provide a blockchain runtime that scales linearly as more miners come into the network providing seamless economies of scale. The cornerstone of the ZILLIQA architecture is based on three main principles: sharding, efficient consensus, smart contracts
In Sharding we Trust
The idea of sharding has been around distributed systems for decades but its relatively new to the blockchain ecosystem. Companies like Ethereum have been working on its version of this concept to address the performance issues that keep plaguing their blockchain network. ZILLIQA has been built with sharing as a first class citizen. In ZILLIQA, the network is divided — into smaller consensus groups called shards each capable of processing transactions in parallel. For instance, if a ZILLIQA network has is say 8000 miners, the platform automatically creates 10 sub-networks each of size 800 miners, in a decentralized manner without a trusted coordinator.
In the ZILLIQA model, different shards can process different transactions without overlapping or double-spending. This is enable by a key component of the ZILLIQA architecture known as the Directory Service Committee(DSC) which is a federation of nodes within the network that are responsible for assigning transactions to specific shards.
The core of ZILLIQA’s consensus protocol relies on practical byzantine fault tolerance (PBFT). In PBFT, all the nodes within a consensus group are ordered in a sequence, and it has one primary node (or leader) and the others are referred to as backup nodes. Every round of PBFT three main phases:
ZILLIQA improves upon classic PBFT by using a multi-signature model that aggregates different signatures into a single signature that is a fraction of the size of the aggregate. Furthermore, the ZILLIQA consensus protocol only requires 2/3 of the nodes in the shard to sign a specific transaction before its committed.
A New Smart Contract Language
A new type of blockchain requires new types of smart contracts! ZILLIQA’s smart contracts are based on SCILLA, a new language that borrows some of the ideas behind Solidity but adapts them to the ZILLIQA blockchain. The ZILLIQA smart contract language is based on four fundamental principles:
A ZILLIQA smart contract looks like the following:
(owner : address,
max_block : uint,
goal : uint)
(* Mutable state description *)
backers : address ⇒ uint = ;
funded : boolean = false;
(* Transition 1: Donating money *)
(sender : address, value : uint, tag : string)
(* Simple filter identifying this transition *)
if tag == "donate"⇒
bs ←& backers;
blk ← && block_number;
let nxt_block = blk + 1 in
if max_block ≤ nxt_block
then send (<to → sender, amount →0,
msg →"deadline_passed">, MT)
The ZILLIQA platform includes its own token known as ZILs. The network provides a finite supply of ZILs capped at 21 billion that will be distributed over the next decade. ZILLIQA also includes many governance policies to guarantee that all participants in the network can benefit from the value of ZILs.
A New Type of Blockchain
ZILLIQA is part of the second generation of blockchain that are building upon the lessons learned by platforms like Ethereum. In addition of providing a robust architecture that address some of the performance limitations of its predecessors, ZILLIQA has built in principles such as fairness and correctness at the core of the platform’s protocols. If the team continues executing towards that vision, ZILLIQA can become one of the protagonists in the next phase of the blockchain platform ecosystem.