Polkadot PoC-2 is here: Parachains, runtime upgrades, and Libp2p networking

Polkadot Network
Published in
4 min readJul 17, 2018


Two months after Polkadot’s first proof of concept went live, PoC-2 is here. This major milestone reached by the Polkadot team provides the working testnet with many new features to be included in the final release, including parachains, staking rewards and slashing, a Libp2p implementation, and much more.

Polkadot aims to solve many of the issues facing blockchains today, including scalability, interoperability, and efficient upgrade mechanics using built-in governance. The release of PoC-2 today marks a major step toward releasing Polkadot in Q3 2019.

At 18:49 (London), 17 July, the network stakeholders successfully performed an on-chain governance-based upgrade of the global testnet from PoC-1 to PoC-2. Polkadot founder Gavin Wood said, “As far as I know, this marks the first major attempt at an on-chain protocol upgrade in the wild.”

What’s in PoC-2?

After PoC-1’s successful launch with accomplishments including a relay chain testnet, an easy-to-use user interface, and additional staked validators, PoC-2 includes some of Polkadot’s most anticipated features.

Co-finalisation of Parachains

Parachains are the blockchains native to Polkadot’s relay chain. By connecting to the relay chain, Parachains benefit from pooled security in that they have their own Turing-complete validation mechanism plus the finalisation mechanism of Polkadot’s much more secure relay chain. Parachains, unlike current generation blockchains, can run whichever governance model and state-transition function they want, with the addition of being able to freely communicate with other Parachains on Polkadot.

With the release of PoC-2, the first parachains can now attach themselves to the relay chain. They come with basic parachain state-transition and validity functions, as well as an initial parachain consensus mechanism.

The first parachains will be deployed during the lifetime of the PoC-2 network by the Polkadot team, but other teams are welcome to submit their own which can be voted on by the on-chain governance system.

New features for a secure, user-friendly network

The PoC-2 testnet includes some necessary upgrades in order to create a healthy Proof-of-Stake network. Validators who seal valid blocks for the relay chain will start to get rewarded for their work in securing the Polkadot network. However, validators who don’t do their job (by being offline or acting maliciously) need to be punished for the system to work, so PoC-2 includes the capability of “slashing” a validator’s stake.

Another new feature for the runtime allows users of Polkadot to have human-readable, 2-byte addresses such as “5Polka” by indexing them. This allows for a much easier way to interact with other users over the network, as well as saving space in transactions.

Libp2p networking

A major upgrade in PoC-2 is the move of the networking technology from Ethereum’s Devp2p to Libp2p, a highly extensible and generic networking stack. It cannot only communicate over raw TCP, but also run directly in the browser via websockets. Polkadot is the first real-world use of the Rust implementation of Libp2p.

Its protocol negotiation system allows for upgrades to be easily implemented while still supporting older versions. This aspect not only aligns with the plan to forklessly upgrade blockchains built into Polkadot and Substrate, but also reinforces Polkadot’s mission to enable innovation in every area of the blockchain space.

Polkadot will enable innovation in consensus system development, and Libp2p’s generic peer-to-peer platform is an ideal fit for future-proofing networking development.

Further updates

The Polkadot client v0.2 now has improvements in disk space management with state pruning in the trie database, and also allows users to import and export their blockchains.

Users can also go to https://telemetry.polkadot.io to monitor network stats.

Upgrading your node

If you’re already validating on PoC-1, use this guide to start validating on PoC-2.

If you’re not yet on the Polkadot testnet and would like to run a node, follow the instructions here.

Polkadot 1.0 on schedule for Q3 2019

After many long hours of developing the next generation of blockchain technology, Polkadot is on track to be released in the third quarter of 2019. By bridging chains together, Polkadot aims to solve major scalability issues that blockchains have been facing, and bring about a new wave of interoperability, security, innovation, and functionality for the decentralised web.

Want to join in Polkadot development and community, and help make an irrepressible Web 3.0 a reality?