The Great Inter-Chain Battle (part 2 )


Similarly to Cosmos, Polkadot also aims to decouple the consensus mechanism from the application layer of a Blockchain in order to be able to connect ledgers.

There are four basic roles in the upkeep of a The Polkadot network: collator, fisherman, nominator and validator. The Polkadot Whitepaper discusses that in one possible implementation of Polkadot, the validator role may actually be broken down into two roles: basic validator and availability guarantor, but we will only talk about the first four roles.

taken from

As the name says, the Validators purpose is to validate new blocks in the Network and run a high availability and bandwidth Relay chain client (depicted below). To become a Validator, a node must deposit a bond which will act as an insurance that the Validator will act without malicious intentions. Nodes can also nominate Validators, paying part of the required deposit and receiving a pro-rata increase or reduction in their deposit according to the bond’s growth to which they contribute. These are called the Nominator nodes.

Transaction Collators, or Collators for short, are actors that maintain a full-node of a parachain and suggest new blocks for Validators to validate, winning a part of the block reward. This prevents Validators from having to be aware of the full state of each and every parachain.

Fisherman exists only to catch malicious entities on the Network. The name stems from the fact that these actors only exist to try and fish out illegal acts on the Network, sending proof of these acts to Validator nodes and winning rewards by doing so. Fisherman must also post a small bond in order to (or Collators for short) prevent sybil attacks from wasting Validators’ time and resources.

Just like Cosmos, Polkadot also allows external Blockchains to connect to the Network. This is achieved by connecting Blockchains to the Network through what Polkadot Whitepaper calls bridges, similar to Cosmos’ Peg-zones.

As seen above, Polkadot also implements a Relay chain, which, similarly to Cosmos Hub, is the glue that holds the Network of parachains together. The Validators work inside the Relay chain, connecting the different parachains together and allowing for assets to change between chains.


Although both Cosmos and Polkadot are still in development, they provide a really good insight into what the future may look like in the Blockchain world. These (and other) technologies are making the future of Blockchain look so promising and exciting!

If you happen to be in London on the 25th of September and want to see how these two technologies fair against each other, join us on the Blockchain Developers Club — Cosmos vs Polkadot.

Be sure to check the resources below to learn more about these two technologies and on Blockchain Interoperability.


Grayblock — Interoperability, the Holy Grail of Blockchain Jackson Palmer — What is a cross-chain protocol? (Cosmos, Polkadot, Interledger) Cosmos Whitepaper Cosmos Blog — Understanding the Value Proposition of Cosmos Polkadot Whitepaper Polkadot Lightpaper Dave Kajpust — Blockchain Interoperability: Cosmos vs. Polkadot

This post was written by Tomás Carvalho developer at Blocksmith.

Blocksmith is supporting BCDC and other Blockchain related events in London. We are a blockchain development studio that helps startups and corporates use blockchain technology to solve real business problems by developing innovative solutions.

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Come down to the BCDC: Cosmos vs Polkadot