Browse and Discovery

5 min

Browse and Asset Discovery

Two different "discovery" features exist in Litmus Edge. Don't confuse them.

1. Asset Discovery (network-level)

Scans your network for assets that aren't yet configured in DeviceHub. Returns IP addresses, vendor / model hints, and protocol guesses.

API folder: DeviceHub -> Asset Discovery

Per-interface scan: eth0, wlan0, etc.

Operations: GET /devicehub/assetdiscovery/... (REST)

Enable / disable scanning per interface

Use when: "I have a new PLC plugged into the same VLAN - what's its IP and what protocol does it speak?"

2. Browse (device-level)

Walks the address space of an already-configured device and surfaces tags / nodes you can import.

API folder: DeviceHub -> Browse

GraphQL operations on /devicehub/v2

Operates against a Device ID (the device must already exist)

Use when: "I have an OPC UA server configured - show me every node so I can pick which ones to monitor."

Browse modes per driver

The 146 drivers vary in what they support:

Mode	What it does	Drivers
Browse	One-shot full address space walk	OPC UA Advanced, AB Logix, Siemens S7CommPlus, ~38 total
DynamicBrowse	Re-browse on demand for changing address spaces	Subset of Browse-capable drivers
StreamBrowse	Incremental walk for large servers	OPC UA Advanced primarily

Drivers without Browse support (e.g. Modbus, since Modbus has no enumeration capability) cannot use the Browse chain - tags must be created directly via CreateRegisters.

The Generator driver (simulator) doesn't support Browse either. If you're using the Generator for testing, skip the Browse chain.

Browse workflow

CreateBrowseTask -> StartBrowseTasks -> [poll] ListBrowseTasks
  -> BrowseTask_GetFoldersForTreeView -> BrowseTask_GetFolderItems
  -> Cart_AddItems (optional Cart_UpdateProperties)
  -> Cart_CreateAllRegisters

7 steps, all on /devicehub/v2. See Browse - Bulk Tag Discovery workflow.

Useful side endpoints

Download Browse Tags (GET /devicehub/browsing/download_csv/task/{task_id}) - exports discovered tags to CSV before committing. Lets users review in Excel before creating.

Upload CSV (REST) - import tags from CSV (skip Browse entirely if you already have the spreadsheet).