What is IPFS? Content-addressed file sharing

IPFS, the InterPlanetary File System, is a peer-to-peer protocol for sharing content through content identifiers. A conventional web address points to a location on a server; IPFS emphasizes the identity of the requested data.

Supporting copies on multiple computers does not mean that every participant automatically stores every file. Continued access requires reachable copies. IPFS is not itself a blockchain or a promise of free, unlimited archival storage.

Example: Retrieving a presentation from either computer

A teacher adds a presentation to IPFS, and two computers retain the data for the same identifier. If the first computer is offline, a student may retrieve the accessible copy from the second. If both remove the file, keeping the identifier is not enough: an identifier cannot recreate a missing copy.

Updating the presentation can produce a different identifier. Import and encoding choices also affect identity, not just the visible file contents. A durable publishing arrangement therefore needs both version management and someone responsible for retention.

Sources

• IPFS persistence
• IPFS content addressing