Free Tool

Healthcare Integration Topology Builder Diagram HL7, FHIR & DICOM networks

Map your integration engine, EHR, PACS, lab, and database as a network topology — with labeled HL7 v2/MLLP, FHIR, SQL, and DICOM connectors. Runs in your browser. No account. Export to PDF or JSON.

Launch the topology builder → See example topologies

Runs in your browser
No account, no upload
PDF + JSON export
PHI stays local

What is an integration topology diagram?

An integration topology diagram is the map of which clinical systems exchange data with which — and over which protocol and port. It shows the integration engine as the hub, with the EHR, lab, PACS, pharmacy, and database as spokes, and a labeled connector (HL7 v2, FHIR, SQL, or DICOM) on every link.

Integration teams draw one before a build, an interface migration, or a security review — it is the single artifact that shows, at a glance, every interface and how clinical data flows through the organization. This tool lets you draw that map in minutes and export it for a runbook or SOW appendix.

Reference healthcare topologies

Common integration patterns you can sketch in the tool. Each is a real-world topology — an integration architecture diagram for healthcare — with labeled HL7, FHIR, and DICOM connectors.

Epic ADT feed through a Mirth Connect hub
Lab orders & results (ORM / ORU)
Imaging: modality → PACS → EHR
SMART-on-FHIR app → Epic
Multi-hospital HIE feed

Map your whole integration network

Drag in pre-labeled nodes for every system in a healthcare integration environment. Each node type is ready to drop on the canvas:

Integration Engine — Mirth Connect, Open Integration Engine (OIE), Rhapsody, Cloverleaf, Corepoint
EHR / EMR — Epic, Cerner / Oracle Health, MEDITECH
PACS / Imaging — DICOM archives and modalities
Lab / LIS — laboratory orders and results systems
Database — SQL Server, PostgreSQL, Oracle
Pharmacy, File Share (SMB/NFS), Application Server, and a Custom node

Labeled connectors for every healthcare protocol

Connect systems with labeled lines showing the protocol and port, with colorblind-accessible line patterns so connection types are distinguishable without relying on color.

Protocol	Transport	Port	Used for
HL7 v2	MLLP	2575 / 6661	Orders, results, ADT (ORM, ORU, ADT, DFT)
FHIR R4	REST / HTTPS	443	Modern APIs, SMART-on-FHIR apps
DICOM	DIMSE / C-STORE	104 · 11112	Imaging — modalities, PACS, viewers
SQL	TDS / JDBC	1433 · 5432	Direct database reads/writes
SMB / CIFS	SMB	445	File-drop interfaces (HL7 batch, PDFs)
HTTPS	REST / SOAP	443	Web services, cloud APIs

See the MLLP protocol reference for HL7 v2 transport details, or the FHIR R4 integration service for REST APIs.

Point-to-point vs hub-and-spoke

Wire every system directly to every other and you get interface spaghetti — N systems can need up to N×(N−1)/2 interfaces. Route everything through a central interface engine instead and each system keeps one connection while the engine handles transformation and routing. Hub-and-spoke is the standard for healthcare integration, and the tool makes the contrast obvious.

Point-to-point — every system wired to every other

Hub-and-spoke — one connection per system, engine at the center

Interface engines for healthcare: a comparison

Every reference topology above puts an interface engine at the hub. These are the engines you'll most often diagram — all speak HL7 v2 natively; FHIR and DICOM support varies by version and edition.

Engine	License	HL7 v2	FHIR	DICOM
Mirth Connect / OIE	Open source	Native	Varies	Varies
Rhapsody	Commercial	Native	Varies	Varies
Cloverleaf	Commercial	Native	Varies	Varies
Corepoint	Commercial	Native	Varies	Varies
Qvera (QIE)	Commercial	Native	Varies	Varies
Iguana	Commercial	Native	Varies	Varies

A “Varies” rating means FHIR or DICOM support depends on the engine’s version and edition and may require an add-on — confirm against your target release. Choosing or migrating an engine? See OIE vs BridgeLink vs Mirth Connect and Mirth Connect alternatives.

Diagram EHR/EMR integration: Epic, Cerner & MEDITECH

Drop a vendor-specific EHR node and wire it to the engine to sketch an EHR integration topology: an Epic ADT feed, a Cerner / Oracle Health results interface, a MEDITECH orders flow. Pair the EHR with a FHIR R4 gateway for SMART-on-FHIR apps, or an HL7 v2/MLLP interface for classic messaging.

How to draw a healthcare integration diagram

1
Drag nodes onto the canvas. Add a node for each system — integration engine (Mirth/OIE/Rhapsody), EHR/EMR, PACS, lab/LIS, database, pharmacy.
2
Connect two nodes. Draw a connector between systems and pick the protocol — HL7 v2, FHIR R4, SQL, SMB, or HTTPS.
3
Label the protocol and port. Each connector shows its protocol and port (e.g. HL7 v2 over MLLP :2575) with a colorblind-accessible line pattern.
4
Export to PDF or JSON. Export a print-ready vector PDF for runbooks and SOW appendices, or JSON to re-import and version-control. Everything stays in your browser.

Export to vector PDF & JSON

Export a print-ready vector PDF for SOW appendices, runbooks, and architecture reviews, or a portable JSON file you can re-import and version-control. Diagrams persist in your browser between visits.

Your data stays in your browser

Diagrams live in your browser's local storage and are never uploaded — which is exactly why healthcare IT teams use it instead of pasting real architecture into a cloud diagramming app. It's a free, PHI-safe alternative to Visio, Lucidchart, and draw.io, built for healthcare integration. No account, no install, nothing leaves your computer.

Frequently asked questions

What is a healthcare integration topology diagram?

A map of which clinical systems exchange data with which — and over what protocol and port. It shows your integration engine, EHR, PACS, lab, and database as nodes, with labeled connectors (HL7 v2/MLLP, FHIR, SQL, DICOM) between them. Teams draw one before a build, migration, or security review.

What is an interface engine?

An interface engine (or integration engine) is the hub that connects clinical systems. It does three things: ingest messages from a source (an EHR, lab, or modality), transform them to the format the destination expects, and route them to one or more downstream systems. Mirth Connect, the Open Integration Engine (OIE), Rhapsody, and Cloverleaf are common examples. In a topology diagram the engine is the hub every spoke connects to.

What's the difference between point-to-point and hub-and-spoke integration?

Point-to-point wires every system directly to every other system, so N systems can need up to N×(N−1)/2 interfaces — the "interface spaghetti" that becomes unmaintainable as you grow. Hub-and-spoke routes everything through a central interface engine, so each system has one connection (to the hub) and the engine handles transformation and routing. Hub-and-spoke is the standard for healthcare integration.

What is an HL7 interface?

An HL7 interface is a connection that exchanges HL7 v2 messages (ADT, ORM, ORU, SIU, DFT, MDM) between two healthcare systems, almost always over the MLLP protocol. It is the most common interface type in a hospital, and the integration engine is what stands up, transforms, and monitors it.

Is there a free tool to diagram HL7 and FHIR integration networks?

Yes — this Topology Builder is 100% free. It runs entirely in your browser, needs no account, and nothing is uploaded. Drag in nodes for your integration engine, EHR, PACS, and labs, connect them with labeled HL7 v2, FHIR R4, SQL, SMB, or HTTPS links, and export to vector PDF or JSON.

Is there a free alternative to Visio for healthcare diagrams?

Yes. This tool is a free, in-browser alternative to Visio (and to Lucidchart/draw.io) built specifically for healthcare integration — its node and connector palettes are pre-loaded with EHR, PACS, integration-engine, HL7, FHIR, and DICOM vocabulary, so you draw an accurate diagram far faster than with a vendor-neutral tool. No license, no account, exports to vector PDF and JSON.

What protocols and ports does an HL7 or FHIR interface use?

HL7 v2 runs over MLLP (commonly port 2575 or 6661); FHIR R4 runs over REST/HTTPS on 443; DICOM uses DIMSE/C-STORE on 104 or 11112; SQL on 1433 (SQL Server) or 5432 (PostgreSQL); SMB/CIFS file drops on 445. Each connector in the tool is labeled with its protocol and port.

Does my diagram data leave my browser?

No. Diagrams are stored in your browser's local storage and never uploaded to a server. You can export a diagram to PDF or JSON to share it, but nothing leaves your computer unless you choose to export and send it — which is exactly why healthcare IT teams use it instead of pasting real architecture into a cloud diagramming app.

Can I diagram Mirth Connect, OIE, and Rhapsody topologies?

Yes. The integration-engine node is pre-labeled for Mirth Connect, the Open Integration Engine (OIE), and Rhapsody. Add EHR (Epic/Cerner/MEDITECH), database, lab/LIS, PACS, pharmacy, and custom nodes, then wire them with the protocol and port that matches your environment.

Can I export the diagram to PDF or Visio?

You can export a print-ready vector PDF (ideal for SOW appendices, runbooks, and architecture reviews) and a portable JSON file you can re-import or version-control. There is no native Visio export; the vector PDF and JSON cover documentation and sharing.

Is this a network diagram tool or an auto-discovery scanner?

It is a manual diagramming tool — you draw the logical integration topology yourself. It does not scan or auto-discover your network, which is deliberate: nothing touches your environment and no data leaves your browser.

Why Saga built this

We diagram these networks for every HL7, FHIR, and DICOM engagement, and we build the custom healthcare software that runs on top of them. This is the tool we use, made free. Talk to our integration team →