Anonymous web authentication with Stellar blockchain

Every application that involves blockchain transactions and is facing the web needs to authenticate users somehow and, surprisingly so, the majority of these offerings still rely on traditional ways of HTTP-based authentication: email-password pair or a social media login through OAuth or similar access delegation standards. Our challenge transaction performs a single Manage Data operation and uses an invalid sequence number to prevent it from being executed on a ledger: as we only leverage certain features of Stellar Protocol to perform one-off authentication, we don’t want to mutate the whole blockchain. If you are interested in blockchain solutions and ever felt a need to authenticate your customers anonymously and securely, please feel free to study the Stellar Web Authentication proposal (note it is pretty much a living specification at the moment, but the general approach is not subject to change) and borrow from our demo implementation in JavaScript and Node.js.

Source: evilmartians.com