# IETF working group chair and RFC author

Source: https://startwithidentity.com/experts/hannes-tschofenig/
Last updated: 2026-09-20
License: content by Start with Identity. Cite the source URL.

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## Bio

Hannes Tschofenig has co-chaired the IETF OAuth working group and the ACE working group on authentication and authorization for constrained environments, alongside SCITT, KEYPROV, DIME, and ECRIT, and has contributed to more than 90 RFCs. His employers have included Siemens, Nokia, and the European Data Protection Supervisor.

Profile built from public IETF records.

## Where their work shows up

Chairing is invisible work that determines what ships: which drafts advance, which objections are load-bearing, and when a working group stops arguing. The OAuth working group produced [OAuth 2.0](https://startwithidentity.com/standards/oauth-2-0/) and the extension stack around it under that kind of stewardship. The ACE work matters separately, because a sensor with kilobytes of RAM cannot run the same authorization flows a browser can, and [machine identity](https://startwithidentity.com/guides/fundamentals/what-is-machine-identity/) at device scale depends on profiles that fit. See the [machine identity guides](https://startwithidentity.com/guides/machine-identity/).