The report
NVIDIA's October 21 Sentry technical report describes a policy boundary implemented on BlueField-4 data processing units instead of relying on the AI-agent host. DOCA Tower would route network and model traffic through a policy gateway, while DOCA Argus adds out-of-band visibility of processes and microVMs through memory introspection. The design aims to preserve evidence and enforce egress policy even when host software is compromised.
The isolation principle is distinct from a monitor running with the same privileges as the agent it reviews. It also brings explicit tradeoffs: a policy processor needs accurate workload identity, full coverage of permitted traffic paths and a credible mapping from signals to allowed effects. NVIDIA's article claims millisecond-scale containment, but provides a vendor description rather than an independently measured multi-tenant deployment study. Sentry's availability was planned for the following year, so it should not be presented as universally deployed remediation for October's observed incidents. NVIDIA architecture report.
An independent monitor still needs a complete view
A DPU-enforced gateway may remain active when the host's agent process is hostile, which changes the attacker's ability to edit the monitor itself. The architecture nevertheless needs a trustworthy mapping from a request to the workload identity and user delegation that authorized it. An out-of-band trace can document a forbidden command without preventing an unmediated local filesystem change; similarly, network policy cannot enforce what it never sees. NVIDIA describes planned components and rapid containment, not independently observed production prevention across those routes. Sentry technical design.