--- { "title": "Managing Multi-Clinic Data and Real-time Synchronization with OrgBAC and Subscriptions", "description": "Managing multiple clinics is hard: every facility needs autonomy, but the network still needs oversight and real-time data flow. OrgBAC and Subscriptions in Aidbox make this easy with automatic isolation and instant event delivery.", "date": "2025-12-09", "author": "Aleksandr Penskoi", "reading-time": "7 minutes", "tags": [ "System Design", "Aidbox" ] } --- Healthcare organizations often manage complex hierarchical structures — regional hospital networks comprising diverse facilities that must balance shared resources with organizational autonomy. Additionally, many clinic-specific healthcare systems need event-driven architecture for real-time data synchronization across interconnected entities. Aidbox solves these challenges with two powerful features: [Organization-Based Hierarchical Access Control (OrgBAC)](https://www.health-samurai.io/docs/aidbox/access-control/authorization/scoped-api/organization-based-hierarchical-access-control) and [Topic-Based Subscriptions](https://www.health-samurai.io/docs/aidbox/modules/topic-based-subscriptions/aidbox-topic-based-subscriptions). ## OrgBAC: Hierarchical Data Isolation OrgBAC allows you to represent an organizational hierarchy inside [Aidbox FHIR server](https://www.health-samurai.io/fhir-server) and provides FHIR API endpoints with automatic data isolation. Imagine a healthcare network such as: - **MedCorp HQ** (parent organization with full access to all data across the network)**City General Hospital** (branch with limited access restricted to their own organizational data) - **Riverside Clinic** (branch with limited access restricted to their own organizational data) To illustrate this, the bundle below shows how each organization in the hierarchy is created through the REST API: ```javascript POST /fhir resourceType: Bundle type: batch entry: - request: method: PUT url: Organization/med-corp resource: name: MedCorp HQ resourceType: Organization - request: method: PUT url: Organization/city-general-hospital resource: name: City General Hospital resourceType: Organization partOf: reference: Organization/med-corp - request: method: PUT url: Organization/riverside-clinic resource: name: Riverside Clinic resourceType: Organization partOf: reference: Organization/med-corp ``` Each gets a dedicated endpoint: - `/Organization/med-corp/fhir` for MedCorp HQ - `/Organization/city-general-hospital/fhir` for City General Hospital - `/Organization/riverside-clinic/fhir` for Riverside Clinic Any resource created through an organization’s endpoint is automatically tagged with its organization ID, ensuring proper isolation without any additional configuration: ```javascript PUT /Organization/city-general-hospital/fhir/Patient/pt-123 name: [ { family: 'John' } ] --- meta: extension: - url: https://aidbox.app/tenant-organization-id valueReference: reference: Organization/city-general-hospital id: pt-123 resourceType: Patient name: - family: Smith ``` The underlying access logic is simple and predictable: - MedCorp HQ sees everything from all branches (`GET /Organization/med-corp/fhir/Patient`) - City General sees only its own data (`GET /Organization/city-general-hospital/fhir/Patient`) - Riverside sees only its own data (`GET /Organization/riverside-clinic/fhir/Patient`) For more details about OrgBAC features and configuration, see the documentation: [Organization-Based Hierarchical Access Control (OrgBAC)](https://www.health-samurai.io/docs/aidbox/access-control/authorization/scoped-api/organization-based-hierarchical-access-control) ## Topic-Based Subscriptions: Real-Time Events Subscriptions enable real-time data synchronization through webhooks, Kafka, and various message queues. Beginning with [Aidbox 2509](https://www.health-samurai.io/docs/aidbox/overview/release-notes#september-2025-stable-2509), subscriptions automatically respect organizational boundaries. When subscription is created through an organization's API, it inherits hierarchical filtering rules. This ensures: - **Hierarchical Flow**: MedCorp HQ's subscription captures events from all branches - **Scoped Topics**: City General's and Riverside's subscriptions only receive their own events - **Security**: Events never leak between sibling organizations Two key components are required for setup: - **AidboxSubscriptionTopic** - defines what types of events should trigger notifivations. The example below captures every final Observation across the entire MedCorp network: ```javascript POST /Organization/med-corp/fhir/AidboxSubscriptionTopic { "resourceType": "AidboxSubscriptionTopic", "url": "http://aidbox.example/observation-feed", "status": "active", "trigger": [{ "resource": "Observation", "fhirPathCriteria": "status = 'final'" }] } ``` - **AidboxTopicDestination** – specifies where to send notifications. Each organization has its own destination created through its dedicated endpoint. The following bundle demonstrates how these destinations are created through the REST Console. ```javascript POST / resourceType: Bundle type: batch entry: # MedCorp HQ destination - receives events from entire network - request: method: POST url: /Organization/med-corp/fhir/AidboxTopicDestination resource: id: med-corp-observation-feed resourceType: AidboxTopicDestination meta: profile: ["http://aidbox.app/StructureDefinition/aidboxtopicdestination-webhook-at-least-once"] kind: webhook-at-least-once topic: http://aidbox.example/observation-feed parameter: - name: endpoint valueUrl: https://med-corp-hq.requestcatcher.com/test # City General Hospital destination - receives only its events - request: method: POST url: /Organization/city-general-hospital/fhir/AidboxTopicDestination resource: id: city-general-observation-feed resourceType: AidboxTopicDestination meta: profile: ["http://aidbox.app/StructureDefinition/aidboxtopicdestination-webhook-at-least-once"] kind: webhook-at-least-once topic: http://aidbox.example/observation-feed parameter: - name: endpoint valueUrl: https://city-general-hospital.requestcatcher.com/test # Riverside Clinic destination - receives only its events - request: method: POST url: /Organization/riverside-clinic/fhir/AidboxTopicDestination resource: id: riverside-observation-feed resourceType: AidboxTopicDestination meta: profile: ["http://aidbox.app/StructureDefinition/aidboxtopicdestination-webhook-at-least-once"] kind: webhook-at-least-once topic: http://aidbox.example/observation-feed parameter: - name: endpoint valueUrl: https://riverside-clinic.requestcatcher.com/test ``` You can monitor requests received by each organization using the following URLs (open them before producing events): - [https://med-corp-hq.requestcatcher.com](https://med-corp-hq.requestcatcher.com/) - [https://riverside-clinic.requestcatcher.com](https://riverside-clinic.requestcatcher.com/) - [https://city-general-hospital.requestcatcher.com](https://city-general-hospital.requestcatcher.com/) The diagram below illustrates how event flows through the system. Green arrows show MedCorp HQ event flow, while yellow arrows show City General Hospital event flow: ![](image-1.avif) ### Test it yourself via REST Console - Create a patient: ```javascript POST /Organization/city-general-hospital/fhir/Patient id: pt-1 name: [{"family": "Smith"}] ``` - Create an observation: ```javascript POST /Organization/city-general-hospital/fhir/Observation resourceType: Observation status: final code: coding: - system: http://loinc.org code: 15074-8 display: Glucose [Moles/volume] in Blood subject: reference: Patient/pt-1 valueQuantity: value: 6.3 unit: mmol/l system: http://unitsofmeasure.org code: mmol/L ``` - Check that http://med-corp-hq.requestcatcher.com and https://city-general-hospital.requestcatcher.com should receive observation create events. ## Conclusion OrgBAC and [topic-based subscriptions](/blog/topic-based-subscriptions-top-5-use-cases-for-digital-health) together create a robust foundation for multi-tenant healthcare architectures. This combination delivers immediate value: - **Hierarchical oversight**: Parent organizations monitor all branches while each facility maintains data autonomy - **Zero-configuration isolation**: Data boundaries are enforced automatically - no manual access control needed - **Real-time synchronization**: Critical events flow instantly to dashboards, billing, and quality systems - **Built-in security**: Organizational boundaries prevent data leakage between sibling facilities - **Developer efficiency**: Native FHIR compliance without custom middleware or complex infrastructure Whether you're architecting a regional hospital network, managing multiple clinics, or building a multi-practice EHR, Aidbox provides a secure, scalable foundation your healthcare system needs. [Start using a free developer license](https://www.health-samurai.io/docs/aidbox/getting-started) to implement OrgBAC and topic-based subscriptions in your organization, or [explore the documentation](https://www.health-samurai.io/docs) for detailed implementation guides. See also: [RBAC with Keycloak and SMART on FHIR V2](/blog/implementing-role-based-access-control-for-fhir-resources-with-keycloak-and-smart-on-fhir-v2).