KeyShield: A Scalable and Quantum-Safe Key Management Scheme

While encryption is powerful at protecting information, it critically relies upon the mystery/private cryptographic key's security. Poor key management would compromise any robust encryption algorithm. In this way, securing information is reduced to the issue of securing such keys from unauthorized access. In this work, KeyShield is proposed, a scalable and quantum-safe key management scheme. KeyShield provides the highest security level as it relies on the impossibility of finding a unique solution to an underdetermined linear system of equations. KeyShield achieves the rekeying using a single broadcast message, called a secure lock, in an open channel rather than pairwise secure channels. Security analyses for a list of attacks are provided, along with a detailed discussion on the quantum-safe feature. KeyShield outperforms state-of-the-art schemes in several aspects, including quantum-resistance, computation cost, message overhead, storage cost, and rekeying delay.