Public Index Network is a blockchain host that powers the Open Index Protocol ("OIP") and other application-layer software. OIP is an open source specification designed for creating a persistent worldwide index and file library. It is useful for data publishing, file distribution, and facilitating direct payments. With Public Index Network and distributed networking, OIP operates without a central authority. The decentralized network collectively handles record indexing, file storage/distribution, and transaction management. OIP stands out as the first permissionless system with a decentralized and transparent index for digital content and protected file persistence. The system follows a Salutary Protocol model, which provides financial incentives to both the application and protocol layers. This ensures the sustainability and antifragility of the system by aligning all participants through open market incentives.