Kusama (KSM)

Overview & History

Kusama is an early, experimental version of Polkadot that exists as an independent network. It intends to act as a sandbox for developers, allowing teams to deploy and test pre-release versions of their projects before launching them on Polkadot's mainnet. Kusama will also serve as a testbed for Parity Technologies leading up to the mainnet launch of Polkadot. Like its sister chain, Kusama uses a native token, KSM, to power computation and give holders the ability to participate in securing the network and voting on upgrade proposals.

Roadmap

Kusama Chain Candidate 1 (CC1)

Date: August 2019. Type: Network Launch

Kusama is an early, unaudited and unrefined release of Polkadot. It is a separate chain acting as a "canary" network for Polkadot to test out the governance, staking, and sharding, as well as allowing teams and developers to build and deploy a Parachain, under real economic conditions

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Kusama Chain Candidate 2 (CC2)

Date: September 2019. Type: Software Release

This upgrade technically created a new chain (compared to CC1) and included several key fixes. All CC1 transactions were included in the CC2 chain, so user accounts were unchanged.

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Kusama Chain Candidate 2 (CC2): PrePoS

Date: October 2019. Type: Software Release

CC2 went through a runtime upgrade to prepare the network for a switch to a Nominated Proof-of-Stake system, replacing its Proof-of-Authority predecessor. Nominated PoS later became a reality with the release of Polkadot v0.6.17. This version also introduced the Council elections module, which allowed participants to elect other stakeholders to the Kusama Council (the network’s on-chain governance system). Another release, v0.6.18, upgraded GRANDPA to version 0.10.0 and included other new features.

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Kusama Chain Candidate 3 (CC3)

Date: November 2019. Type: Software Release

On a granular level, it incorporates on-chain authority discovery, a move to prefixed storage mappings, and a revamp of the network’s governance system.

Kusama's new decentralized, on-chain governance system eventually passed Referendum 4, which removed Sudo requirements and unlocked KSM token transfers.

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Failed Runtime Upgrade

Date: January 2020 Type: Vulnerability

As Kusama attempted a runtime upgrade to version 1034, a naming issue bricked the chain. The Polkadot team responded by issuing a series of updates to revert the chain, reject the faulty upgrade, and subsequently speed the chain back up (a so-called "time warp"), so Kusama would not live in the past. The canary network returned to a normal, non-warp speed state on Jan. 12, eight days after the failed runtime upgrade.