Zilliqa, the public blockchain project has taken numerous strides in the first quarter of 2019. The project’s mainnet launched on January 31, 2019, and was one of its many moments of success in the first four months of 2019. After speaking to Zilliqa’s Marketing Lead Saiba Kataruka n March 2019, BlockchainReporter got the opportunity to speak to the project’s co-founder and Chief Technological Officer (CTO), who touched on Zilliqa’s protocol, some of its challenges and how the team plans to overcome them.

BR: How would you, in simple terms, describe Zilliqa’s consensus protocol?

The consensus protocol that Zilliqa relies on is called Practical Byzantine Fault Tolerance, or PBFT. In very simple terms, PBFT is a voting protocol where miners are able to vote on the validity of a block, after which, all transactions within that block then have valid signatures, providing finality to the consensus decision. This eliminates the possibility of a double spend attack.

PBFT provides very strong “agreement” guarantees. In particular, it ensures that at the end of the protocol, all honest nodes are in agreement even when malicious nodes attempt to mislead by sending different votes to different honest nodes. The protocol, in fact, requires several rounds of voting, whereby, the network can be assured that each honest node has validated a block and that every honest node knows that every other honest node has validated the block.

One key point to note here is that since PBFT is essentially a voting protocol, one must make sure that Sybil attacks are prevented, otherwise, it may become possible for a malicious node to skew the voting process by spawning multiple nodes. To that end, we use Proof-of-Work (PoW) as a sybil resistance mechanism. So, in order for a node to become a miner, it has to first perform a PoW which acts an entry ticket to the network. Once the node is a part of the network, it validates blocks using PBFT.

BR: Scalability is a huge problem when it comes to blockchain solutions. How does Zilliqa aim to overcome this issue?

Zilliqa’s approach to tackling scalability is enabled by our use of sharding technology. On our platform, we make use of network, transaction, and smart contract sharding, allowing for greater efficiencies in transaction processing, while ensuring that the network is able to scale accordingly and is sufficiently secured. Sharding can be best described as a “divide and conquer” strategy––rather than tasking all the nodes with the responsibility of processing all the transactions in the network, nodes are automatically divided into groups. These smaller groups are then responsible for processing a subset of transactions on the network, making the entire process much more efficient. To understand more about the specificities of our sharding technology, I highly recommend that you read this detailed blogpost.

Though many scaling solutions exist in the industry today, ranging from alternative consensus protocols such as delegated Proof-of-Stake to the implementation of sidechains, our team has found that sharding is a viable scaling solution that enables us to strike a balance between scalability, decentralisation, and security. As a layer 1 scaling solution, sharding ensures that our network scales securely, as the blockchain can operate with security guarantees provided by itself.

BR: What benefits can miners expect while mining Zilliqa?

There are several benefits miners can expect while mining on Zilliqa. In part due to the design of our consensus protocol, one of the greatest benefits lies in the fact that mining on Zilliqa is comparatively more eco-friendly and cost-effective when compared to other protocols. By limiting the use of PoW for the purposes of miner verification to mitigate Sybil attacks, the role of PoW in our consensus protocol is significantly reduced. Miners will only need to run PoW every two to three hours, meaning that GPUs will only need to run at full load for a very short time, leading to a much lower energy footprint when compared to legacy PoW blockchains.

Moreover, miners on Zilliqa also have the opportunity to dual-mine an Ethash-based PoW blockchain such as Ethereum. As opposed to “winner takes all” models on PoW blockchains, Zilliqa’s mining rewards are based on each miners’ contributions of valid signatures, allowing for a much more equitable distribution of rewards. Along with such cost benefits, miners on Zilliqa also benefit from the network’s linear scaling property which means that the ratio of mining costs and the number of transactions processed remains constant––as the network grows, miners will not be burdened by rising transaction processing costs.

BR: How does Zilliqa leverage the use of smart contracts?

Zilliqa is a smart-contract platform like Ethereum, hence allowing application developers to write contracts that can capture business and application logic. The core protocol, however, does not rely on smart contracts unlike some of the existing scaling solutions for Ethereum that apparently use a smart contract to manage block validators.

Zilliqa employs a new smart contract language named Scilla which has been designed to eliminate many known vulnerabilities in existing contracts such as re-entrancy due to a contract calling another contract in the middle of function execution. More generally, the language is principled in the sense that it cleanly separates its computation and communication components. The language design will also make it easier (compared to contracts written in languages such as Solidity) to provide mathematical guarantees on the safety and correctness of a Scilla contract.

BR: What does 2019 have in store for the Zilliqa community?

2019 is a critical year for Zilliqa. Following our announcement that we would be powering Hg Exchange, we launched our mainnet at the end of January, making us the first public blockchain in the world to successfully utilise sharding technology. As the culmination of all of our hard work, our aspirations, and our dreams, the launch of our mainnet is a significant milestone on our roadmap. Within the next few weeks, our mainnet will be coming out of its bootstrap phase and will be enabling transaction processing functionalities. Thereafter, the long-awaited token swap will also take place––for more information regarding participating exchanges and wallets, please refer to this blogpost.

We also hope to see our anchor Dapps going live on the platform, such as BOLT, Hg Exchange, and the numerous blockchain games that we have in the pipeline. During this time, the community can also expect to see more enhancements on our core protocol while we simultaneously work to provide more tools for developers looking to build on Zilliqa and program in our secure-by-design, smart contract language, Scilla.

We’ll continue to engage with the global developer community by participating in events and hosting more workshops and meetups. Moreover, blockchain education remains a key priority at Zilliqa. We believe that engaging with new generations of talent will be essential to sustained growth and innovation for the wider industry as a whole. We recently launched our new education initiative, Blockchain A-Z, in partnership with King’s College London’s student-led KCL Blockchain society. Throughout 2019, the workshop series will expand to the University of Oxford along with other universities in the United Kingdom.

Not only the year of realization for our team, but 2019 is also a year of outreach and engagement. As our network continues to mature, we want to encourage more developers to come on board and build with us. With support and enthusiasm from our developer community, we hope to see a more vibrant, sophisticated ecosystem on the network come to life.