Polygon Launches Testnet Bridge to Enable Low-Cost Layer 2s

Introduction to Web 3.0 and Blockchain

Avail, a blockchain network, has recently launched a testnet data availability bridge to Ethereum, as per the announcement on July 7th. Once the testing phase is complete, developers will be able to create “validiums” or low-cost layer 2s which do not store full transaction data on Ethereum.

Avail was originally a part of Polygon Labs, but was later spun off as an independent project in March. Anurag Arjun, the co-founder of Polygon, is also the founder of Avail.

Layer-2 rollup networks such as Optimism, Arbitrum, Polygon zkEVM, and zkSync Era reduce transaction fees by combining transactions into compressed “rollups” and periodically adding them to the base layer. However, this process requires that all transactions be written to the base layer, which often leads to higher transaction fees than layer-1 competitors.

To solve this issue, some networks have opted to write only the validation proofs of each transaction to the base layer, while storing the full transaction data off-chain. This type of network is referred to as a “validium”. For instance, StarkEx has a validium mode that stores data with a Data Availability Committee (DAC) instead of Ethereum. Polygon proof-of-stake may become a validium which stores data on a proof-of-stake chain in 2024.

Web 3.0 Blockchain for Data Availability

The new bridge announced by Avail allows developers to quickly and easily create custom validiums by storing their transaction data on the Avail network, thus eliminating the need to create their own DAC or proof-of-stake data availability network. When users try to move cryptocurrency from layer 2 back to the base layer of Ethereum, Avail’s bridge will transmit an attestation that the data is available on Avail, thus allowing the withdrawal to occur.

“The launch of the Data Availability attestation bridge is a major step forward in our mission to optimize blockchain scalability and efficiency,” said Arjun. “By supporting rollup constructions in validium, optimistic chains, and volition modes, we are not only reducing costs but also paving the way for a more inclusive and efficient layer-2 and layer-3 Web 3.0 ecosystem.”

Arjun previously told Cointelegraph that data availability solutions will become essential to the Web 3.0 space as zero-knowledge proof rollups become more widely used.