Explore a cutting-edge approach to blockchain scalability in this 20-minute conference talk presented at the 2018 IEEE Symposium on Security & Privacy. Dive into OmniLedger, a secure, scale-out, decentralized ledger that utilizes sharding to achieve Visa-level transaction processing capabilities while maintaining security and decentralization. Learn about innovative techniques such as bias-resistant public-randomness for shard selection, cross-shard commit protocols for atomic transactions, and optimizations including parallel intra-shard processing and ledger pruning. Discover how OmniLedger addresses the challenges of scaling permissionless distributed ledgers, achieving linear throughput scaling with the number of validators and confirming transactions in under two seconds.