• Signatures with Tight Multi-user Security from Search Assumptions 

      Pan, Jiaxin; Ringerud, Magnus (Peer reviewed; Journal article, 2020)
      We construct two tightly secure signature schemes based on the computational Diffie-Hellman (CDH) and factoring assumptions in the random oracle model. Our schemes are proven secure in the multi-user setting, and their ...
    • Signed Diffie-Hellman Key Exchange with Tight Security 

      Pan, Jiaxin; Qian, Chen; Ringerud, Magnus (Peer reviewed; Journal article, 2021)
      We propose the first tight security proof for the ordinary two-message signed Diffie-Hellman key exchange protocol in the random oracle model. Our proof is based on the strong computational Diffie-Hellman assumption and ...
    • WalnutDSA: Another attempt at braid group cryptography 

      Ringerud, Magnus (Master thesis, 2019)
      Hovedformålet med denne oppgaven er å studere det digitale signatursystemet WalnutDSA, som ble foreslått til det amerikanske National Institute of Standards and Technology (NIST) sin ``Post-Quantum Cryptography Standardization'' ...