Blockchain apps often need to handle large files (videos, AI datasets, game assets, NFT media) that don’t fit on-chain. Traditional chains like Ethereum or Sui replicate all data to every validator, which works for small state but makes storing big blobs prohibitively expensive. In practice, most heavy data today still sits on centralized clouds (AWS, Google, etc.), creating a “Web3 paradox”: you own an NFT on-chain but its image or video may disappear if a centralized host fails. To bridge this gap, dedicated decentralized storage systems (IPFS/Filecoin, Arweave) emerged, but many rely on full replication (storing many identical copies), leading to 25× overhead or more for high durability.
Walrus tackles this problem by decoupling heavy data from on-chain logic. In Walrus, large files (“blobs”) are split into smaller pieces called slivers and stored across many independent nodes around the world, while the Sui blockchain keeps metadata (who owns what) and proofs of availability. Instead of copying a 10GB file to dozens of machines, Walrus uses its novel “Red Stuff” erasure-coding scheme to store only enough redundant pieces to recover the file even if many nodes go offline.
This dramatically reduces waste: you pay for one file plus a few encoded backups, not 20 full copies. In effect, Walrus provides the reliability and censorship-resistance of blockchain with far lower storage costs. Developers get a storage layer where every file is provable on-chain, yet the bulky content lives in a scalable, cost-effective network of nodes (with Sui coordinating ownership and payments)
