Ethereum

\1 The major cost of running a rollup is pushing its data to a DA (data availability) layer.

\2 Ethereum is a preferred DA layer for rollups for many (due to its security properties), but its storage is very expensive.

\4 While the temporary nature of this new storage makes it unusable for actual Ethereum transactions, it's perfect for storing rollup data.

\5 All rollups that use Ethereum as a DA layer, will eventually start using this temporary storage instead of the expensive permanent one. That is expected to reduce their DA cost by an order of magnitude.

\6 Lower cost of running a rollup -> lower rollup transaction fees for the users! 🚀

\3 EIP-4844 introduces temporary storage in Ethereum at a drastically cheaper price.