Ramazan Eles 
Ethereum’s core developers have successfully implemented the Dencun upgrade on the mainnet, ushering in the era of “blobs” that are poised to significantly reduce transaction costs for Layer 2 transactions.
The activation of the upgrade, including the EIP-4844, occurred on the network at epoch 269568, around 10 am ET.
With the implementation of Dencun, Ethereum Layer 2 rollups can now utilize blobs instead of the traditional “calldata” method for posting transactions. This change offers a direct avenue for reducing fees and passing on these savings to end users.
Blobs represent a major enhancement to Ethereum’s infrastructure, aiming to improve data availability without disrupting the current framework. By doing so, they help decrease transaction costs on Layer 2 solutions such as Base, Optimism, Arbitrum One, zkSync, Starknet, and others. A dedicated fee market for blobs will strive to maintain low transaction costs for Layer 2 networks, even during periods of high network congestion.
While some Layer 2 chains are planning to integrate blobs immediately, others may take some time to adopt this new feature.
Additional Improvements Introduced by Dencun
In addition to EIP-4844, the Dencun upgrade brings eight other code updates to the Ethereum network.
One notable improvement is EIP-4788, which introduces an “enshrined oracle” to facilitate communication between Ethereum’s execution layer and consensus layer.
Another significant enhancement is EIP-1153, which focuses on “transient storage,” a critical feature necessary for the launch of Uniswap version 4 later this year.