The Update Framework (TUF) is a specification implementation that secures software update systems through cryptographic signatures and verification mechanisms. The framework provides both server and client components that enable publishers to create and manage trusted collections of content. Publishers can sign their content offline using secure keys and distribute signed trusted collections through notary servers. TUF addresses security vulnerabilities in TLS-based communications by enabling content verification even when communicating with potentially compromised servers or insecure mirrors. The system allows consumers to verify content authenticity using publisher public keys obtained through secure channels. The framework is integrated into Docker Content Trust (DCT) and provides mechanisms for content publishers to sign their releases while enabling consumers to verify content integrity. TUF includes comprehensive service architecture documentation and has been actively developed since November 2015.