Trust Slope Validation Across Zone Migration: Continuity Verification With Quarantine

Mechanism

Zone migration begins when a workload running or staged within a sending zone is selected for transfer to a receiving zone. Selection may be driven by residency policy, by load redistribution, by a workload-internal request to follow a data dependency that resides in the receiving zone, or by an operator-initiated relocation. Regardless of the trigger, the migration protocol proceeds through three structurally distinct phases: a sealing phase at the sending zone, a transit phase across the substrate fabric, and an admission phase at the receiving zone. Each phase produces a cryptographically committed artifact that becomes part of the workload's lineage, so that the migration is not a hidden infrastructure event but a first-class entry in the workload's auditable trajectory.

In the sealing phase, the sending zone's migration controller computes a terminal lineage root over the workload's chain as it stands at the moment of departure, signs a sealing record under the zone's migration key, and binds the sealing record to a transit envelope that names the intended receiving zone. The sealing record fixes the workload's outbound posture: its declared role, the slope record produced by its most recent propagation step, the governance envelope under which it was admitted at the sending zone, and the migration key identifier that the receiving zone must resolve to verify the seal. Once sealed, the workload is no longer eligible for execution within the sending zone; the sending zone's executors refuse to instantiate any workload whose lineage shows a sealing record without a corresponding return-from-migration entry. This refusal is structural, not advisory: it derives from the same admission discipline that governs all other zone-edge decisions, and it ensures that a workload cannot be both migrating and executing simultaneously across zones, which would otherwise create the possibility of divergent state.

In the transit phase, the sealed workload propagates across the substrate fabric under the platform's pseudonymous propagation primitive. The transit envelope is opaque to intermediate substrates: they observe a propagation handle, append their attestation receipts to the lineage chain in the usual way, and forward the workload toward the receiving zone. Intermediates do not, and cannot, evaluate the migration's admissibility; that evaluation is reserved for the receiving zone. The transit phase is therefore not a privileged path but a recognised path, and the workload remains under the same propagation invariants that govern non-migrating traffic. A consequence of this design is that migration latency is a function of substrate-fabric latency rather than of any centralised migration coordinator, and migration tolerates partition, reorder, and intermittent connectivity to the same extent that the propagation primitive does.

In the admission phase, the receiving zone's structural validator inspects the arriving workload as it would inspect any admitting workload, but with three additional checks specific to migration. The first additional check is seal verification: the validator resolves the migration key identifier against the receiving zone's trust set of recognised peer zones, verifies the sealing signature, and confirms that the sealed terminal root agrees with the chain that has arrived. The second additional check is slope continuity across the transition: the validator computes the slope between the sealed posture and the receiving zone's expected admission posture, evaluates the result against the inter-zone tolerance vector negotiated between the two zones, and decides whether the transition is continuous, quarantine-eligible, or refused. The third additional check is migration-depth conformance: the validator inspects the chain for the count of prior migration entries and refuses workloads whose accumulated migration depth exceeds the receiving zone's configured maximum.

When all three checks pass, the validator emits an admission entry that explicitly references the sealing record by hash, completing the cryptographic handoff. The admission entry is appended to the workload's lineage chain, and the chain now contains a paired sealing-admission record that any later auditor can verify in isolation: the seal proves that the sending zone released the workload with a particular outbound posture, and the admission proves that the receiving zone accepted the workload under a verified continuation of that posture. This pairing is the mechanism by which cross-zone routes become audit-required: a workload whose chain shows execution in two zones without a corresponding seal-admission pair is, by construction, an inconsistent artifact whose downstream consumption will fail at any conforming validator.

When slope continuity falls within the quarantine band rather than within the continuity band, the workload is admitted into a quarantine envelope rather than into the receiving zone's general execution surface. The quarantine envelope permits the workload to make progress only against operations that produce no externally observable effects: the workload may compute, may consult its own state, and may emit lineage entries reflecting its progress, but it may not settle, may not transmit to non-quarantined substrates, and may not reply to upstream requests. Quarantine resolution is performed by an out-of-band review pathway whose decision, accept-and-promote or reject-and-refuse, is itself signed and appended to the chain. Quarantine is therefore not a hidden holding pen but an auditable state of the workload, and the resolution decision is part of the workload's permanent record. When slope discontinuity exceeds the quarantine band, the workload is refused outright, the receiving zone emits a refusal entry that references the seal, and the sending zone is notified through a return-channel attestation so that any operational response, such as quarantining other workloads from the same sender or revisiting the inter-zone tolerance, can be undertaken with full provenance.

Migration is bounded by construction. The migration-depth cap prevents a workload from accumulating an unbounded sequence of zone transitions that would defeat audit by sheer chain length. The chain-compaction discipline that applies to propagation applies equally to migration: a workload approaching its compaction window has the granular prefix of its chain compacted into a signed summary, and the migration entries within the compacted prefix are preserved as summary statistics that retain the migration-depth count and the zone-traversal sequence. The bound on quarantine resolution time prevents an adversary from inducing indefinite suspension by producing workloads whose slope sits exactly at the boundary of the quarantine band. Together, these bounds ensure that migration consumes resources proportional to legitimate workload behaviour and that the cost of evaluating a migrating workload is predictable from its declared posture.

Operating Parameters

The inter-zone tolerance vector is a per-pair parameter negotiated between the sending and receiving zones and published as a signed artifact in both zones' configuration. The vector specifies, dimension by dimension, the slope deviation that the receiving zone is prepared to admit as continuous, the deviation it will admit only into quarantine, and the deviation it will refuse outright. Tolerance is generally tighter for transitions into zones with stricter governance posture and looser for transitions into zones with comparable or more permissive posture, reflecting the principle that admission into a stricter zone requires stronger evidence of trajectory continuity. The vector is versioned, and the version in force at the time of a migration is recorded in the admission entry so that an auditor replaying the decision can resolve it against the negotiated tolerance that applied at that moment.

Migration-depth caps are configured per zone and reflect the operator's tolerance for accumulated migration history. A typical deployment caps depth at a small integer for high-assurance workloads and at a larger integer for routine workloads, with the cap recorded in the receiving zone's admission policy and consulted at admission time. When a workload's migration depth approaches the cap, the receiving zone may admit the workload only into a constrained execution envelope that prohibits further migration, ensuring that the depth bound is respected without prematurely refusing the workload. Workloads that have reached the cap and require further migration must instead undergo a controlled re-origination at a designated zone, which produces a fresh chain and a documented transition record rather than an additional migration entry.

Quarantine envelopes are parameterised by their permissible operation set, the maximum duration before automatic refusal, the witness configuration that observes quarantine progress, and the resolution authority empowered to promote or refuse quarantined workloads. The permissible operation set is drawn from a fixed enumeration that excludes any operation with externally observable effect, and the enumeration is part of the platform's operation vocabulary rather than a per-deployment configuration. The maximum duration is configurable but bounded above by a platform-level ceiling, ensuring that quarantine cannot be used as an indefinite holding state. Witness configuration determines which third-party observers, if any, are entitled to attest to quarantine progress, supporting regulated deployments in which a quarantine review must be observable to an external party.

Migration keys are scoped per zone and per peer-zone relationship, with rotation schedules independent of validator and propagation salt schedules. Rotation events are published into the lineage verification path so that sealing records signed under historical keys remain verifiable indefinitely. Compromise of a migration key is treated as a peer-relationship incident: pending migrations under the compromised key are quarantined at the receiving zone, future seals require rotation, and the affected pair of zones may renegotiate their tolerance vector in light of the incident. Independence of rotation schedules ensures that a single rotation event does not invalidate in-flight migrations across the entire substrate fabric.

The chain-compaction discipline preserves migration-specific summary statistics. When a chain prefix containing migration entries is compacted, the compaction summary records the number of migration entries compacted, the sequence of zones traversed within the compacted prefix, the cumulative slope traversed across those migrations, and the keys under which the corresponding seals were signed. These statistics are sufficient for downstream validators and auditors to compute migration-depth and zone-traversal properties without expanding the compacted prefix, and they are sealed under the compaction authority's signature so that the act of summarisation is itself part of the chain.

Return-channel attestations are sent from the receiving zone to the sending zone whenever a migration is refused or whenever a quarantined workload is ultimately refused on resolution. The attestation includes the sealing-record hash, the failure code, the policy version under which the decision was made, and the receiving zone's signature. The sending zone records received attestations in its own audit log and may use them to update its operational posture, for example by quarantining future workloads from the same upstream substrate or by alerting an operator. Return-channel delivery is best-effort but is itself audit-tracked: a missing return attestation is observable and may be requested explicitly through the receiving zone's audit interface.

Alternative Embodiments

In a first alternative embodiment, the cryptographic handoff is performed under a threshold signature scheme in which the sending zone's seal requires concurrence of multiple migration controllers and the receiving zone's admission requires concurrence of multiple validators. The threshold variant suits deployments in which neither zone is willing to grant unilateral migration authority to a single component, such as multi-party federations in which a regulator and an operator each hold a share of the migration key. Threshold seals and admissions are recorded in the chain with the share identifiers that participated, supporting later audit of which controllers and validators were involved in each transition.

In a second embodiment, the slope-continuity check across the transition is performed against a richer dimensional space that includes the residency obligations of the data referenced by the workload. This embodiment is appropriate where migration must respect data-residency constraints that are not captured by the standard governance envelope, and where a workload that is structurally continuous in its own posture may nonetheless be discontinuous in the residency posture of its data. The richer check requires a registered data-obligation vocabulary shared between the participating zones.

In a third embodiment, the quarantine envelope is implemented on a dedicated quarantine substrate that is physically segregated from the receiving zone's general execution surface. The dedicated substrate provides stronger isolation guarantees against side-channel observation and is used in deployments where quarantine must not share resources with general execution. The dedicated-substrate variant retains the same admission, resolution, and audit discipline as the in-zone quarantine envelope, differing only in the physical hosting of the workload during quarantine.

In a fourth embodiment, return-channel attestations are replaced by witness publication: rather than the receiving zone delivering an attestation directly to the sending zone, both zones publish their respective records to a shared witness service that maintains a Merkle log of cross-zone migrations. The witness variant suits federations in which direct return channels are impractical or where a third-party log is required for regulatory reasons. The witness service is constrained to publication and is not granted any role in admission or seal evaluation.

In a fifth embodiment, the migration-depth cap is replaced by a migration-budget that consumes proportional to the slope deviation observed at each transition. A workload whose successive migrations are all close to continuity consumes little budget and may migrate many times; a workload whose migrations approach the quarantine band consumes budget rapidly and is constrained to fewer migrations. The budget variant captures the operator's intuition that frequent low-deviation migrations are tolerable while infrequent high-deviation migrations warrant tighter bounding.

In a sixth embodiment, the receiving zone's admission emits, alongside the standard admission entry, a signed reasoning trace that records which clauses of the inter-zone tolerance vector were consulted and how each evaluated. The reasoning trace supports audit obligations that require explanation in addition to outcome, and it is structured so that an auditor can analyse migration-decision discipline without being granted access to the workload's payload.

In a seventh embodiment, migration is staged through an intermediate transit zone that performs no execution but provides a cryptographically verified holding state for workloads in transit between mutually distrusting zones. The transit zone seals an intermediate admission entry and re-seals the workload outbound, producing a chain that explicitly records the intermediate hop. This embodiment supports asymmetric trust topologies in which the sending and receiving zones do not directly recognise each other's migration keys but each recognises the transit zone.

Composition With the Cognition-Native Execution Platform

Zone migration interlocks tightly with pseudonymous propagation. The transit phase of migration is implemented as a propagation episode under the standard propagation primitive, so that intermediates handle migrating workloads under exactly the same unlinkable-handle and slope-record discipline as non-migrating workloads. Migration therefore inherits the propagation primitive's unlinkability properties without additional construction, and the lineage chain that travels with a migrating workload is the same chain produced by propagation, augmented by the sealing and admission entries that mark the migration boundaries. The structural unification of migration with propagation means that no special-case path exists in the substrate fabric for migration traffic, which simplifies the platform's invariant analysis and eliminates a class of bypass attacks that would otherwise target a privileged migration channel.

Migration is admitted at the receiving zone through the structural validator described elsewhere in this disclosure. The validator's standard three-check admission discipline is augmented at migration boundaries by the seal verification, slope continuity, and migration-depth checks described above, but the augmented checks are expressed in the same admission-receipt vocabulary as the standard checks. A downstream consumer reading an admission receipt does not need to know whether the receipt was produced for a migrating or a non-migrating workload; it consumes the receipt under the same rules in either case. This uniformity is what permits cross-zone routes to be audit-required as a structural property: every workload's admission posture is fully captured by its admission receipts, and the receipts produced at migration boundaries are first-class members of that posture.

The platform's deterministic evaluation discipline applies across migration boundaries because the lineage chain is preserved across the transition. Two evaluators presented with the same workload, the same admission receipts, and the same chain reach the same evaluation verdict, regardless of whether the chain spans one zone or several. This determinism is required for the platform's broader replayability and partition-tolerance guarantees, and it is what makes migration safe for workloads whose downstream consumers depend on stable evaluation outcomes. A workload that has migrated multiple times produces the same outcome at consumption as a workload that has remained in a single zone, provided the chain shows admissible continuity at each transition.

Migration composes with the platform's settlement and audit layers through the lineage-chain interface. Settlement events consult the chain's most recent admission receipt and refuse to settle on workloads whose receipt is missing, expired, or signed by a key outside the recognised trust set. Audit events walk the chain end to end, identify migration entries by their structural form, and reconstruct the zone-traversal sequence without requiring access to either zone's internal state. The chain therefore acts as a sufficient artifact for both settlement and audit across migrating workloads, and the platform does not require any side-channel coordination between the settlement layer, the audit layer, and the migration controllers of the participating zones.

Prior-Art Distinction

Conventional virtual-machine and container live-migration systems transfer execution state between hypervisors or orchestrators within a single administrative domain, under the assumption that the source and destination share a trust boundary. They do not evaluate trust slope across the migration, do not emit cryptographically committed admission records, and do not provide a quarantine state for transitions whose admissibility is uncertain. They treat migration as an infrastructure event rather than as an audit-bearing structural transition, and they assume that the receiving host is implicitly trusted to continue executing the workload under whatever invariants applied at the sending host.

Conventional federated single-sign-on and identity-federation protocols transfer principal assertions across administrative domains under signed exchanges, but they address identity, not workload trajectory. They do not propagate stateful workloads, do not maintain a tamper-evident lineage chain across the transition, and do not provide a structural quarantine state for assertions whose continuity with prior posture is uncertain. They are compatible with, but distinct from, the migration primitive disclosed here, and they could in principle serve as a constituent in the inter-zone trust set without altering the migration primitive itself.

Conventional cross-region replication systems in distributed data stores transfer data across administrative regions under signed log shipping, but they treat the data as opaque and do not evaluate the trajectory of any workload that produced or consumes the data. They do not produce paired sealing-admission records, do not evaluate slope continuity, and do not provide an admission gate at the receiving region that can refuse replicated state on structural grounds. They address eventual consistency across regions, not audit-required cross-zone admission.

Conventional service-mesh egress and ingress controllers enforce policy at administrative boundaries through token validation and traffic shaping, but they do not maintain a workload-bound lineage chain that crosses the boundary, do not evaluate slope continuity across the transition, and do not produce admission receipts that compose with downstream settlement and audit. They are operational gates rather than structural primitives, and they assume a token-based identity model that is orthogonal to the workload-trajectory model addressed by the disclosed mechanism.

Conventional quarantine systems in messaging and email infrastructure hold suspect items in an out-of-band store pending review, but they do not produce signed quarantine state, do not append quarantine entries to a tamper-evident chain that travels with the item, and do not bound quarantine resolution within a deterministic budget that is auditable from the chain. The disclosed quarantine envelope differs by being a structural state of the workload, recorded in the chain, with bounded resolution authority and signed promotion or refusal outcomes.

The disclosed migration primitive distinguishes itself by integrating cryptographic seal-admission handoff, slope-continuity evaluation across the transition, structurally enforced cross-zone audit, bounded migration depth, and signed quarantine state within a single mechanism that operates as a deterministic property of the execution substrate. No prior system combines these properties as structural primitives of cross-zone workload transfer.

Disclosure Scope

This disclosure is directed to trust slope validation across zone migration as a structural primitive of the cognition-native execution platform described in US 19/230,933. The scope of the disclosure includes the three-phase migration protocol with sealing, transit, and admission; the cryptographic seal-admission handoff and its integration with the lineage chain; the inter-zone tolerance vector and the slope-continuity discipline that consumes it; the quarantine envelope with bounded operation set and bounded resolution duration; the migration-depth cap and the chain-compaction summary statistics that preserve depth across compaction; and the return-channel attestation discipline that closes the loop between sending and receiving zones.

The disclosure is not limited to any particular cryptographic primitive for sealing, signing, or chain commitment. It is not limited to a particular tolerance representation, depth-cap value, or quarantine-duration ceiling. It is not limited to a particular substrate topology and is intended to apply equally to centralised cloud federations, multi-party regulated federations, and intermittently connected edge federations. The disclosure is similarly agnostic with respect to the transport that carries migrating workloads between zones and applies equally to message-passing, shared-store, and stream-replication transports.

The disclosure expressly contemplates the alternative embodiments enumerated above and any combination of them that is not internally inconsistent. Threshold-signed seals composed with witness publication and dedicated-substrate quarantine are within scope, as are deployments that adopt different combinations of embodiments at different zone boundaries within a single federated substrate. Migration-budget variants, transit-zone staging, and reasoning-trace augmentation are each within scope as embodiments of the disclosed mechanism.

The disclosure is bounded by the requirement that migration operate as a deterministic, audit-required, structural property of the execution substrate, rather than as an advisory protocol layered above it or as an infrastructure event hidden from the workload's audit surface. Implementations that relegate any of the seal-admission handoff, slope-continuity evaluation, or quarantine state to optional middleware fall outside the disclosed scope. Implementations that retain the structural character of the primitive while varying its constituent algorithms remain within scope.