Buldas was a leading contributor to the Estonian Digital Signature Act and
ID-card from 1996 to 2002, currently the only national-level
public-key infrastructure (PKI) which has achieved widespread adoption by a country's population for legally binding digital signatures. He published his first
timestamping related research in 1998 and has published over 30 academic papers on the subject. His experience of implementing a national level PKI led him to invent Keyless Signature Infrastructure, a digital signature/timestamping system for electronic data that uses only hash-function based cryptography. By using hash-functions as the only cryptographic primitive the complexities of key management are eliminated and the system remains secure from quantum cryptographic attacks. His invention led to the founding of keyless signature technology company Guardtime in 2006. He is the Chair of Information Security at
Tallinn University of Technology. Buldas has been a supervisor for 15 MSc dissertations and 4 PhD theses. ==Awards==