The Egress Boundary as a Release Gate: Enforcing No-Egress in Offline Enterprise AI

Abstract. Offline enterprise AI is commonly sold on the promise that data stays local. In practice that promise is usually a policy: a statement of intent, backed by contracts and configuration, that the buyer is asked to trust. This paper argues that for sovereign deployments the property should be treated instead as an engineering invariant, something a component must demonstrate rather than something an operator must trust. We describe three complementary controls. First, a loopback-only inference engine that binds solely to the local host, ships without telemetry, and performs no background update or licence calls, so that in ordinary operation it originates no network traffic at all. Second, an operator-controlled egress gateway that is disabled by default, permits outbound connections only to an explicit allowlist, and records each decision to allow or deny as a sealed entry. Third, and centrally, a release gate that tests a component for network reachability before it is allowed to ship: a build that can reach the network does not pass. We contrast this design with policy-based and endpoint-detection approaches, which observe and react to egress rather than preventing its possibility, and we set out the limits honestly, including covert channels, side channels and the trust that must still be placed in the host kernel and hardware. No-egress, on this account, becomes a testable release criterion rather than an assurance.