In particular, both IKEv2 and TLS 1.3 use Krawczyk’s SIGMA protocol[1] as the cryptographic core of their key exchange procedures.

He has also contributed foundational work in the areas of threshold and proactive cryptosystems and searchable symmetric encryption, among others.

His research includes both theoretical and applied elements of cryptography, with a focus on internet security, privacy, and authentication.

His most recent projects in the area include: TLS 1.3, the new-generation SSL/TLS; HKDF, the standard for key derivation embraced by TLS 1.3, Signal, WhatsApp, Facebook Messenger, and others; and OPAQUE, a password authentication protocol being standardized by the IRTF and recently deployed by Facebook in its implementation of end-to-end encrypted chat backups for WhatsApp.

[2] Krawczyk is the author of many other cryptographic algorithms and protocols including the HMQV key-exchange protocol, the LFSR-based Toeplitz Hash Algorithm, the Shrinking Generator encryption scheme, the UMAC message authentication code, and the randomized hashing scheme for strengthening digital signatures.