Ethereum co-founder Vitalik Buterin spoke on December 3, 2025, minutes after the network’s latest update, Fusaka, was released. This is the second hard fork for Ethereum this year, following Pectra in May.
As CriptoNoticias explained, Fusaka introduced a data validation system known as PeerDAS (Peer Data Availability Sampling).
For Vitalik, this mechanism represents the central component that Vitalik was missing. Ethereum arrives at the actual model of “”Sharding» (data fragmentation), a goal that has been in place since 2015.
Sharding has been a goal for Ethereum since 2015 and data availability sampling since 2017, and we have now achieved it.
Vitalik Buterin, founder of Ethereum.
Buterin recalled that the network tried to split information into pieces so that no node had to download and review all the data.
This idea only works if there is a technique that can guarantee that each fragment is available and complete without each node fully validating it. How (data availability sampling, surveyed since 2017) This is exactly what PeerDAS offers.
PeerDAS allows the network to reach consensus on blocks without the need for individual nodes to see all the data.
Instead, each node takes small random pieces and verifies them through a probabilistic process. If all samples match, we can infer that the block is complete and accessible.
According to Buterin, this approach “Withstands 51% attack”since the validation is done on the client side and does not rely on validator votes.
The contribution is significant. Fragmentation has always tried to make more possible Users can operate nodes without expensive hardwareBut to accomplish this, they needed a system that would ensure the availability of fragmented data without compromising security.
PeerDAS does just that. It reduces the amount of information each node needs to verify while maintaining strong cryptographic guarantees about block integrity.
In practice, this significantly reduces node bandwidth and processing requirements. Additionally, it opens up space to increase the operational capacity of the second layer (L2) network without overloading Ethereum’s main layer (L1).
Furthermore, in a recent interview with CriptoNoticias, Bartek Kiepuszewski, co-founder of L2BEAT, also emphasized that Fusaka: This increases the reliability of the second layer network.
In other words, by increasing the availability of data in L1, L2 Less dependence on external companies To store data.
Three Pending Limits: A path that Buterin considers incomplete.
Despite the progress, Buterin argued that there are “three aspects of Fusaka where sharding is still incomplete.”
- The first one is related to the power available at L2.
Today, L2 networks can already increase their capacity because PeerDAS reduces the amount of data each node needs to verify. This allows for total transaction volume Increases in proportion to the square of the computing power available per node.
However, this advantage does not carry over to Ethereum’s main layer, as all operations must be performed directly.
For L1 to scale equally, a “mature ZK-EVM”, or zero-knowledge cryptographic proof (ZK, zero knowledge).
These tests condense thousands of transactions into a single verifiable receipt, Validate large sets of transactions without reprocessing transactions on each node..
- The second limitation is the so-called Block’s “bottleneck between proposer and constructor”:
In the current architecture, the block constructor must access all data and assemble the entire block before the proposer publishes the block.
Vitalik Buterin is “Distributed assembly of blocks”multiple actors build parts and avoid dependence on a single operator.
This idea points to the Reduce centralization risks The city block construction market is an area with very few participants today.
- The third concern is No fragmented memory pool exists.
mempool is the space in which transactions wait before being included in a block.
For Buterin, this fragmentation Shardingbecause it would be allowed Pre-block flows can also be split and scaled.
Despite these limitations, Buterin called Fusaka’s arrival “a fundamental step in blockchain design.”
Finally, he clarified his priorities for the next two years (at least for now).
We will refine the PeerDAS mechanism, carefully scale it, ensure its stability, use it to scale L2, and once ZK-EVM matures, apply it internally to scale Ethereum L1 gas as well.
Vitalik Buterin, founder of Ethereum.
The co-founders concluded their message by clearly recognizing the continued efforts of Ethereum researchers and core developers, and the progress made during this time. It will take almost 10 years to achieve this goal.