Scalability is one of the primary goals of blockchains, which must balance the need for decentraliztion with the desire to force as much throughput as possible. More scalability equals more use cases, users, and mainstream adoption. But achieving this is harder than it sounds, as blockchain engineers have discovered time and again. It’s fair to say, therefore, that Polkadot’s JAM upgrade has caused quite a stir on account of its scope and the scalability breakthroughs it promises.
Scaling While Retaining Decentralization
The blockchain trilemma famously describes the challenge of achieving three key properties in a system simultaneously: decentralization, security, and scalability. According to the trilemma, a blockchain can optimize for two of these properties but not all three. Polkadot’s JAM upgrade is so extensive that it’s akin to launching an entirely new blockchain protocol. While the focus has been on optimizing for scalability, its architects have also given careful consideration to maintaining decentralization, as we’ll explore shortly.
But first, what’s the deal with JAM? Joint-Accumulate Machine (JAM) was the subject of Dr Gavin Wood’s gray paper which was published in April. It’s as big brain as you’d expect of a visionary of Wood’s caliber, but this isn’t just big picture stuff: it’s a practical blueprint for scaling Polkadot that’s already underway.
What JAM Brings to the Table
Polkadot’s relay chain is tasked with doing a lot of things simultaneously which require enormous processing power. While its current architecture has capably performed its duties up until now, it’s not the easiest system for developers to get to grips with, particularly when they’re seeking to connect to non-parachain services.
JAM will make it much easier for developers to deploy feature-rich dapps that draw data from multiple sources including off-chain feeds. It reduces complexity and allows dapps to be launched faster and with more functionality built in. It takes its cues from the smart contract functionality offered by Ethereum while retaining the shared security model that is a cornerstone of Polkadot parachains.
One of the key features incorporated into JAM is what’s described as a transactionless ecosystem. In other words, JAM itself doesn’t require conventional onchain transactions every time an event occurs, enabling dapps to remain operational provided they have DOT to power them. The real scalability gains, however, come through parallel processing that will allow Polkadot to run hundreds of chains and programs simultaneously, coupled with elastic scaling that will allow the relay chain to dynamically match demand.
Bounty Program Bids to Decentralize JAM
Blockchain technology doesn’t decentralize itself: it requires the efforts of hundreds of independent developers creating standalone points of access to achieve this. Which is the goal of the bounty program commissioned by Web3 Foundation. 10 million DOT and an additional 100,000 KSM have been made available as a prize pool to teams developing JAM clients.
As the current JAM clients explorer explains, “Having multiple independent implementations makes it less likely for a large portion of the network to be affected by the same bug.” There are already dozens of clients under development with the goal of supporting different programming languages that will make it easier for devs to interact with JAM using familiar frameworks.
While JAM is a Polkadot-centric initiative, its deployment will have broader implications for the web3 landscape. Partially in bringing Polkadot closer to existing networks and technologies such as ZK rollups, which it supports, but also in showing that mature blockchains can undergo a major overhaul without incident. Which is why Polkadot is rigorously testing JAM to ensure that its introduction goes smoothly. There’s a lot at stake and a lot of industry figures watching closely to see if JAM can succeed in scaling Polkadot without sacrificing decentralization.
