private boolean isAwsSignedToken(final JwsParts jwsParts) {
        // Request may have come from another stroom node that has passed on an AWS signed
        // token, but not in the special AWS header
        return jwsParts.getHeaderValue(SIGNER_HEADER_KEY)
                .filter(val -> {
                    LOGGER.debug("{} is {}", SIGNER_HEADER_KEY, val);
                    return val.startsWith(AMZN_OIDC_SIGNER_PREFIX);
                })
                .isPresent();
    }
The user claims, in JSON web tokens (JWT) format.
stroom-security/stroom-security-common-impl/src/main/java/stroom/security/common/impl/StandardJwtContextFactory.java