Phase 1 Streams B–E scaffold + Phase 2 Streams A–C scaffold — 8 new projects with ~70 new tests, all green alongside the 494 v1 IntegrationTests baseline (parity preserved: no v1 tests broken; legacy OtOpcUa.Host untouched). Phase 1 finish: Configuration project (16 entities + 10 enums + DbContext + DesignTimeDbContextFactory + InitialSchema/StoredProcedures/AuthorizationGrants migrations — 8 procs including sp_PublishGeneration with MERGE on ExternalIdReservation per decision #124, sp_RollbackToGeneration cloning rows into a new published generation, sp_ValidateDraft with cross-cluster-namespace + EquipmentUuid-immutability + ZTag/SAPID reservation pre-flight, sp_ComputeGenerationDiff with CHECKSUM-based row signature — plus OtOpcUaNode/OtOpcUaAdmin SQL roles with EXECUTE grants scoped to per-principal-class proc sets and DENY UPDATE/DELETE/INSERT/SELECT on dbo schema); managed DraftValidator covering UNS segment regex, path length, EquipmentUuid immutability across generations, same-cluster namespace binding (decision #122), reservation pre-flight, EquipmentId derivation (decision #125), driver↔namespace compatibility — returning every failing rule in one pass; LiteDB local cache with round-trip + ring pruning + corruption-fast-fail; GenerationApplier with per-entity Added/Removed/Modified diff and dependency-ordered callbacks (namespace → driver → device → equipment → poll-group → tag, Removed before Added); Core project with GenericDriverNodeManager (scaffold for the Phase 2 Galaxy port) and DriverHost lifecycle registry; Server project using Microsoft.Extensions.Hosting BackgroundService replacing TopShelf, with NodeBootstrap that falls back to LiteDB cache when the central DB is unreachable (decision #79); Admin project scaffolded as Blazor Server with Bootstrap 5 sidebar layout, cookie auth, three admin roles (ConfigViewer/ConfigEditor/FleetAdmin), Cluster + Generation services fronting the stored procs. Phase 2 scaffold: Driver.Galaxy.Shared (netstandard2.0) with full MessagePack IPC contract surface — Hello version negotiation, Open/CloseSession, Heartbeat, DiscoverHierarchy + GalaxyObjectInfo/GalaxyAttributeInfo, Read/WriteValues, Subscribe/Unsubscribe/OnDataChange, AlarmSubscribe/Event/Ack, HistoryRead, HostConnectivityStatus, Recycle — plus length-prefixed framing (decision #28) with a 16 MiB cap and thread-safe FrameWriter/FrameReader; Driver.Galaxy.Host (net48) implementing the Tier C cross-cutting protections from driver-stability.md — strict PipeAcl (allow configured server SID only, explicit deny on LocalSystem + Administrators), PipeServer with caller-SID verification via pipe.RunAsClient + WindowsIdentity.GetCurrent and per-process shared-secret Hello, Galaxy-specific MemoryWatchdog (warn at max(1.5×baseline, +200 MB), soft-recycle at max(2×baseline, +200 MB), hard ceiling 1.5 GB, slope ≥5 MB/min over 30-min rolling window), RecyclePolicy (1 soft recycle per hour cap + 03:00 local daily scheduled), PostMortemMmf (1000-entry ring buffer in %ProgramData%\OtOpcUa\driver-postmortem\galaxy.mmf, survives hard crash, readable cross-process), MxAccessHandle : SafeHandle (ReleaseHandle loops Marshal.ReleaseComObject until refcount=0 then calls optional unregister callback), StaPump with responsiveness probe (BlockingCollection dispatcher for Phase 1 — real Win32 GetMessage/DispatchMessage pump slots in with the same semantics when the Galaxy code lift happens), IsExternalInit shim for init setters on .NET 4.8; Driver.Galaxy.Proxy (net10) implementing IDriver + ITagDiscovery forwarding over the IPC channel with MX data-type and security-classification mapping, plus Supervisor pieces — Backoff (5s → 15s → 60s capped, reset-on-stable-run), CircuitBreaker (3 crashes per 5 min opens; 1h → 4h → manual cooldown escalation; sticky alert doesn't auto-clear), HeartbeatMonitor (2s cadence, 3 consecutive misses = host dead per driver-stability.md). Infrastructure: docker SQL Server remapped to host port 14330 to coexist with the native MSSQL14 Galaxy ZB DB instance on 1433; NuGetAuditSuppress applied per-project for two System.Security.Cryptography.Xml advisories that only reach via EF Core Design with PrivateAssets=all (fix ships in 11.0.0-preview); .slnx gains 14 project registrations. Deferred with explicit TODOs in docs/v2/implementation/phase-2-partial-exit-evidence.md: Phase 1 Stream E Admin UI pages (Generations listing + draft-diff-publish, Equipment CRUD with OPC 40010 fields, UNS Areas/Lines tabs, ACLs + permission simulator, Generic JSON config editor, SignalR real-time, Release-Reservation + Merge-Equipment workflows, LDAP login page, AppServer smoke test per decision #142), Phase 2 Stream D (Galaxy MXAccess code lift out of legacy OtOpcUa.Host, dual-service installer, appsettings → DriverConfig migration script, legacy Host deletion — blocked by parity), Phase 2 Stream E (v1 IntegrationTests against v2 topology, Client.CLI walkthrough diff, four 2026-04-13 stability findings regression tests, adversarial review — requires live MXAccess runtime).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ClusterNode.cs

@@ -0,0 +1,51 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>Physical OPC UA server node within a <see cref="ServerCluster"/>.</summary>
+public sealed class ClusterNode
+{
+    /// <summary>Stable per-machine logical ID, e.g. "LINE3-OPCUA-A".</summary>
+    public required string NodeId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    public required RedundancyRole RedundancyRole { get; set; }
+
+    /// <summary>Machine hostname / IP.</summary>
+    public required string Host { get; set; }
+
+    public int OpcUaPort { get; set; } = 4840;
+
+    public int DashboardPort { get; set; } = 8081;
+
+    /// <summary>
+    ///     OPC UA <c>ApplicationUri</c> — MUST be unique per node per OPC UA spec. Clients pin trust here.
+    ///     Fleet-wide unique index enforces no two nodes share a value (decision #86).
+    ///     Stored explicitly, NOT derived from <see cref="Host"/> at runtime — silent rewrite on
+    ///     hostname change would break all client trust.
+    /// </summary>
+    public required string ApplicationUri { get; set; }
+
+    /// <summary>Primary = 200, Secondary = 150 by default.</summary>
+    public byte ServiceLevelBase { get; set; } = 200;
+
+    /// <summary>
+    ///     Per-node override JSON keyed by DriverInstanceId, merged onto cluster-level DriverConfig
+    ///     at apply time. Minimal by intent (decision #81). Nullable when no overrides exist.
+    /// </summary>
+    public string? DriverConfigOverridesJson { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public DateTime? LastSeenAt { get; set; }
+
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public required string CreatedBy { get; set; }
+
+    // Navigation
+    public ServerCluster? Cluster { get; set; }
+    public ICollection<ClusterNodeCredential> Credentials { get; set; } = [];
+    public ClusterNodeGenerationState? GenerationState { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ClusterNodeCredential.cs

@@ -0,0 +1,29 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Authenticates a <see cref="ClusterNode"/> to the central config DB.
+///     Per decision #83 — credentials bind to NodeId, not ClusterId.
+/// </summary>
+public sealed class ClusterNodeCredential
+{
+    public Guid CredentialId { get; set; }
+
+    public required string NodeId { get; set; }
+
+    public required CredentialKind Kind { get; set; }
+
+    /// <summary>Login name / cert thumbprint / SID / gMSA name.</summary>
+    public required string Value { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public DateTime? RotatedAt { get; set; }
+
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public required string CreatedBy { get; set; }
+
+    public ClusterNode? Node { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ClusterNodeGenerationState.cs

@@ -0,0 +1,26 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Tracks which generation each node has applied. Per-node (not per-cluster) — both nodes of a
+///     2-node cluster track independently per decision #84.
+/// </summary>
+public sealed class ClusterNodeGenerationState
+{
+    public required string NodeId { get; set; }
+
+    public long? CurrentGenerationId { get; set; }
+
+    public DateTime? LastAppliedAt { get; set; }
+
+    public NodeApplyStatus? LastAppliedStatus { get; set; }
+
+    public string? LastAppliedError { get; set; }
+
+    /// <summary>Updated on every poll for liveness detection.</summary>
+    public DateTime? LastSeenAt { get; set; }
+
+    public ClusterNode? Node { get; set; }
+    public ConfigGeneration? CurrentGeneration { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ConfigAuditLog.cs

@@ -0,0 +1,25 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Append-only audit log for every config write + authorization-check event. Grants revoked for
+///     UPDATE / DELETE on all principals (enforced by the authorization migration in B.3).
+/// </summary>
+public sealed class ConfigAuditLog
+{
+    public long AuditId { get; set; }
+
+    public DateTime Timestamp { get; set; } = DateTime.UtcNow;
+
+    public required string Principal { get; set; }
+
+    /// <summary>DraftCreated | DraftEdited | Published | RolledBack | NodeApplied | CredentialAdded | CredentialDisabled | ClusterCreated | NodeAdded | ExternalIdReleased | CrossClusterNamespaceAttempt | OpcUaAccessDenied | …</summary>
+    public required string EventType { get; set; }
+
+    public string? ClusterId { get; set; }
+
+    public string? NodeId { get; set; }
+
+    public long? GenerationId { get; set; }
+
+    public string? DetailsJson { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ConfigGeneration.cs

@@ -0,0 +1,32 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Atomic, immutable snapshot of one cluster's configuration.
+///     Per decision #82 — cluster-scoped, not fleet-scoped.
+/// </summary>
+public sealed class ConfigGeneration
+{
+    /// <summary>Monotonically increasing ID, generated by <c>IDENTITY(1, 1)</c>.</summary>
+    public long GenerationId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    public required GenerationStatus Status { get; set; }
+
+    public long? ParentGenerationId { get; set; }
+
+    public DateTime? PublishedAt { get; set; }
+
+    public string? PublishedBy { get; set; }
+
+    public string? Notes { get; set; }
+
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public required string CreatedBy { get; set; }
+
+    public ServerCluster? Cluster { get; set; }
+    public ConfigGeneration? Parent { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Device.cs

@@ -0,0 +1,23 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>Per-device row for multi-device drivers (Modbus, AB CIP). Optional for single-device drivers.</summary>
+public sealed class Device
+{
+    public Guid DeviceRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string DeviceId { get; set; }
+
+    /// <summary>Logical FK to <see cref="DriverInstance.DriverInstanceId"/>.</summary>
+    public required string DriverInstanceId { get; set; }
+
+    public required string Name { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    /// <summary>Schemaless per-driver-type device config (host, port, unit ID, slot, etc.).</summary>
+    public required string DeviceConfig { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/DriverInstance.cs

@@ -0,0 +1,32 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>One driver instance in a cluster's generation. JSON config is schemaless per-driver-type.</summary>
+public sealed class DriverInstance
+{
+    public Guid DriverInstanceRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string DriverInstanceId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    /// <summary>
+    ///     Logical FK to <see cref="Namespace.NamespaceId"/>. Same-cluster binding enforced by
+    ///     <c>sp_ValidateDraft</c> per decision #122: Namespace.ClusterId must equal DriverInstance.ClusterId.
+    /// </summary>
+    public required string NamespaceId { get; set; }
+
+    public required string Name { get; set; }
+
+    /// <summary>Galaxy | ModbusTcp | AbCip | AbLegacy | S7 | TwinCat | Focas | OpcUaClient</summary>
+    public required string DriverType { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    /// <summary>Schemaless per-driver-type JSON config. Validated against registered JSON schema at draft-publish time (decision #91).</summary>
+    public required string DriverConfig { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+    public ServerCluster? Cluster { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Equipment.cs

@@ -0,0 +1,64 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     UNS level-5 entity. Only for drivers in Equipment-kind namespaces.
+///     Per decisions #109 (first-class), #116 (5-identifier model), #125 (system-generated EquipmentId),
+///     #138–139 (OPC 40010 Identification fields as first-class columns).
+/// </summary>
+public sealed class Equipment
+{
+    public Guid EquipmentRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    /// <summary>
+    ///     System-generated stable internal logical ID. Format: <c>'EQ-' + first 12 hex chars of EquipmentUuid</c>.
+    ///     NEVER operator-supplied, NEVER in CSV imports, NEVER editable in Admin UI (decision #125).
+    /// </summary>
+    public required string EquipmentId { get; set; }
+
+    /// <summary>UUIDv4, IMMUTABLE across all generations of the same EquipmentId. Downstream-consumer join key.</summary>
+    public Guid EquipmentUuid { get; set; }
+
+    /// <summary>Logical FK to the driver providing data for this equipment.</summary>
+    public required string DriverInstanceId { get; set; }
+
+    /// <summary>Optional logical FK to a multi-device driver's device.</summary>
+    public string? DeviceId { get; set; }
+
+    /// <summary>Logical FK to <see cref="UnsLine.UnsLineId"/>.</summary>
+    public required string UnsLineId { get; set; }
+
+    /// <summary>UNS level 5 segment, matches <c>^[a-z0-9-]{1,32}$</c>.</summary>
+    public required string Name { get; set; }
+
+    // Operator-facing / external-system identifiers (decision #116)
+
+    /// <summary>Operator colloquial id (e.g. "machine_001"). Unique within cluster. Required.</summary>
+    public required string MachineCode { get; set; }
+
+    /// <summary>ERP equipment id. Unique fleet-wide via <see cref="ExternalIdReservation"/>. Primary browse identifier in Admin UI.</summary>
+    public string? ZTag { get; set; }
+
+    /// <summary>SAP PM equipment id. Unique fleet-wide via <see cref="ExternalIdReservation"/>.</summary>
+    public string? SAPID { get; set; }
+
+    // OPC UA Companion Spec OPC 40010 Machinery Identification fields (decision #139).
+    // All nullable so equipment can be added before identity is fully captured.
+    public string? Manufacturer { get; set; }
+    public string? Model { get; set; }
+    public string? SerialNumber { get; set; }
+    public string? HardwareRevision { get; set; }
+    public string? SoftwareRevision { get; set; }
+    public short? YearOfConstruction { get; set; }
+    public string? AssetLocation { get; set; }
+    public string? ManufacturerUri { get; set; }
+    public string? DeviceManualUri { get; set; }
+
+    /// <summary>Nullable hook for future schemas-repo template ID (decision #112).</summary>
+    public string? EquipmentClassRef { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public ConfigGeneration? Generation { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ExternalIdReservation.cs

@@ -0,0 +1,36 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Fleet-wide rollback-safe reservation of ZTag and SAPID. Per decision #124 — NOT generation-versioned.
+///     Exists outside generation flow specifically because old generations and disabled equipment can
+///     still hold the same external IDs; per-generation uniqueness indexes fail under rollback/re-enable.
+/// </summary>
+public sealed class ExternalIdReservation
+{
+    public Guid ReservationId { get; set; }
+
+    public required ReservationKind Kind { get; set; }
+
+    public required string Value { get; set; }
+
+    /// <summary>The equipment that owns this reservation. Stays bound even when equipment is disabled.</summary>
+    public Guid EquipmentUuid { get; set; }
+
+    /// <summary>First cluster to publish this reservation.</summary>
+    public required string ClusterId { get; set; }
+
+    public DateTime FirstPublishedAt { get; set; } = DateTime.UtcNow;
+
+    public required string FirstPublishedBy { get; set; }
+
+    public DateTime LastPublishedAt { get; set; } = DateTime.UtcNow;
+
+    /// <summary>Non-null when explicitly released by FleetAdmin (audit-logged, requires reason).</summary>
+    public DateTime? ReleasedAt { get; set; }
+
+    public string? ReleasedBy { get; set; }
+
+    public string? ReleaseReason { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Namespace.cs

@@ -0,0 +1,31 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     OPC UA namespace served by a cluster. Generation-versioned per decision #123 —
+///     namespaces are content (affect what consumers see at the endpoint), not topology.
+/// </summary>
+public sealed class Namespace
+{
+    public Guid NamespaceRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    /// <summary>Stable logical ID across generations, e.g. "LINE3-OPCUA-equipment".</summary>
+    public required string NamespaceId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    public required NamespaceKind Kind { get; set; }
+
+    /// <summary>E.g. "urn:zb:warsaw-west:equipment". Unique fleet-wide per generation.</summary>
+    public required string NamespaceUri { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public string? Notes { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+    public ServerCluster? Cluster { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/NodeAcl.cs

@@ -0,0 +1,32 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     One ACL grant: an LDAP group gets a set of <see cref="NodePermissions"/> at a specific scope.
+///     Generation-versioned per decision #130. See <c>acl-design.md</c> for evaluation algorithm.
+/// </summary>
+public sealed class NodeAcl
+{
+    public Guid NodeAclRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string NodeAclId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    public required string LdapGroup { get; set; }
+
+    public required NodeAclScopeKind ScopeKind { get; set; }
+
+    /// <summary>NULL when <see cref="ScopeKind"/> = <see cref="NodeAclScopeKind.Cluster"/>; otherwise the scoped entity's logical ID.</summary>
+    public string? ScopeId { get; set; }
+
+    /// <summary>Bitmask of <see cref="NodePermissions"/>. Stored as int in SQL.</summary>
+    public required NodePermissions PermissionFlags { get; set; }
+
+    public string? Notes { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/PollGroup.cs

@@ -0,0 +1,19 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>Driver-scoped polling group. Tags reference it via <see cref="Tag.PollGroupId"/>.</summary>
+public sealed class PollGroup
+{
+    public Guid PollGroupRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string PollGroupId { get; set; }
+
+    public required string DriverInstanceId { get; set; }
+
+    public required string Name { get; set; }
+
+    public int IntervalMs { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/ServerCluster.cs

@@ -0,0 +1,42 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     Top-level deployment unit. 1 or 2 <see cref="ClusterNode"/> members.
+///     Per <c>config-db-schema.md</c> ServerCluster table.
+/// </summary>
+public sealed class ServerCluster
+{
+    /// <summary>Stable logical ID, e.g. "LINE3-OPCUA".</summary>
+    public required string ClusterId { get; set; }
+
+    public required string Name { get; set; }
+
+    /// <summary>UNS level 1. Canonical org value: "zb" per decision #140.</summary>
+    public required string Enterprise { get; set; }
+
+    /// <summary>UNS level 2, e.g. "warsaw-west".</summary>
+    public required string Site { get; set; }
+
+    public byte NodeCount { get; set; }
+
+    public required RedundancyMode RedundancyMode { get; set; }
+
+    public bool Enabled { get; set; } = true;
+
+    public string? Notes { get; set; }
+
+    public DateTime CreatedAt { get; set; } = DateTime.UtcNow;
+
+    public required string CreatedBy { get; set; }
+
+    public DateTime? ModifiedAt { get; set; }
+
+    public string? ModifiedBy { get; set; }
+
+    // Navigation
+    public ICollection<ClusterNode> Nodes { get; set; } = [];
+    public ICollection<Namespace> Namespaces { get; set; } = [];
+    public ICollection<ConfigGeneration> Generations { get; set; } = [];
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/Tag.cs

@@ -0,0 +1,47 @@
+using ZB.MOM.WW.OtOpcUa.Configuration.Enums;
+
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>
+///     One canonical tag (signal) in a cluster's generation. Per decision #110:
+///     <see cref="EquipmentId"/> is REQUIRED when the driver is in an Equipment-kind namespace
+///     and NULL when in SystemPlatform-kind namespace (Galaxy hierarchy preserved).
+/// </summary>
+public sealed class Tag
+{
+    public Guid TagRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string TagId { get; set; }
+
+    public required string DriverInstanceId { get; set; }
+
+    public string? DeviceId { get; set; }
+
+    /// <summary>
+    ///     Required when driver is in Equipment-kind namespace; NULL when in SystemPlatform-kind.
+    ///     Cross-table invariant enforced by sp_ValidateDraft (decision #110).
+    /// </summary>
+    public string? EquipmentId { get; set; }
+
+    public required string Name { get; set; }
+
+    /// <summary>Only used when <see cref="EquipmentId"/> is NULL (SystemPlatform namespace).</summary>
+    public string? FolderPath { get; set; }
+
+    /// <summary>OPC UA built-in type name (Boolean / Int32 / Float / etc.).</summary>
+    public required string DataType { get; set; }
+
+    public required TagAccessLevel AccessLevel { get; set; }
+
+    /// <summary>Per decisions #44–45 — opt-in for write retry eligibility.</summary>
+    public bool WriteIdempotent { get; set; }
+
+    public string? PollGroupId { get; set; }
+
+    /// <summary>Register address / scaling / poll group / byte-order / etc. — schemaless per driver type.</summary>
+    public required string TagConfig { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/UnsArea.cs

@@ -0,0 +1,21 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>UNS level-3 segment. Generation-versioned per decision #115.</summary>
+public sealed class UnsArea
+{
+    public Guid UnsAreaRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string UnsAreaId { get; set; }
+
+    public required string ClusterId { get; set; }
+
+    /// <summary>UNS level 3 segment: matches <c>^[a-z0-9-]{1,32}$</c> OR equals literal <c>_default</c>.</summary>
+    public required string Name { get; set; }
+
+    public string? Notes { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+    public ServerCluster? Cluster { get; set; }
+}

src/ZB.MOM.WW.OtOpcUa.Configuration/Entities/UnsLine.cs

@@ -0,0 +1,21 @@
+namespace ZB.MOM.WW.OtOpcUa.Configuration.Entities;
+
+/// <summary>UNS level-4 segment. Generation-versioned per decision #115.</summary>
+public sealed class UnsLine
+{
+    public Guid UnsLineRowId { get; set; }
+
+    public long GenerationId { get; set; }
+
+    public required string UnsLineId { get; set; }
+
+    /// <summary>Logical FK to <see cref="UnsArea.UnsAreaId"/>; resolved within the same generation.</summary>
+    public required string UnsAreaId { get; set; }
+
+    /// <summary>UNS level 4 segment: matches <c>^[a-z0-9-]{1,32}$</c> OR equals literal <c>_default</c>.</summary>
+    public required string Name { get; set; }
+
+    public string? Notes { get; set; }
+
+    public ConfigGeneration? Generation { get; set; }
+}