# Distinguished Engineer

Source: https://startwithidentity.com/experts/brian-campbell/
Last updated: 2026-08-29
License: content by Start with Identity. Cite the source URL.

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## Bio

Brian Campbell is one of the most consistent IETF identity contributors of the modern era. His name appears across OAuth 2.0 token binding, DPoP, and many JWT-adjacent specifications. Distinguished Engineer at Ping Identity.

Profile built from public IETF records. Vendor affiliation disclosed.

## Where their work shows up

Campbell's contributions cluster around the hardest remaining problem in [OAuth](https://startwithidentity.com/standards/oauth-2-0/): bearer tokens are replayable by whoever holds them. [DPoP](https://startwithidentity.com/glossary/dpop/) binds a token to a key the client proves possession of, which is the direct answer to [token theft](https://startwithidentity.com/glossary/token-theft/) from browsers and infostealer logs. See also [mTLS](https://startwithidentity.com/glossary/mtls/) for the sender-constraining approach where you control the transport.