Polygon brings you a trustless two-way transaction channel between Polygon and Ethereum by introducing the cross-chain bridge with Plasma and PoS security. With this users can transfer tokens across Polygon without incurring third-party risks and market liquidity limitations. The Plasma and PoS Bridge is available on both Mumbai as well as Mainnet.
Polygon bridge provides a scaling solution which is near-instant, low-cost, and quite flexible. Polygon uses a dual-consensus architecture(Plasma + Proof-of-Stake (PoS) platform) to optimise for speed and decentralisation. We consciously architected the system to support arbitrary state transitions on our sidechains, which are EVM-enabled.
There is no change to the circulating supply of your token when it crosses the bridge;
- tokens that leave ethereum network are locked and the same number of tokens are minted on Polygon as a pegged token (1:1).
- To move the tokens back to the ethereum network, tokens are burned on Polygon network and unlocked on ethereum network during the process.
PoS vs Plasma
|PoS Bridge(Recommended)||Plasma Bridge|
|Short description||DApp Developers looking for flexibility and faster withdrawals with POS system security||DApp Developers looking for increased security guarantees with Plasma exit mechanism.|
|Structure||Highly flexible||Rigid, Less Flexible|
|Deposit(Ethereum → Polygon)||22-30 mins||22-30 mins|
|Withdrawal(Polygon → Ethereum)||1 checkpoint = ~ 30 mins to 6 hours||Call to the process-exit procedure on Ethereum's contract.|
|Security||Proof-of-Stake system, secured by a robust set of external validators.||Polygon’s Plasma contracts piggybacks on Ethereum’s security.|
|Support Standards||ETH, ERC20, ERC721, ERC1155 and Others||Only ETH, ERC20, ERC721|