Docs · Spec · GDS
GDS — Global Discovery Server
Global Discovery Server — central registry of OPC UA servers in a plant. One typed structure (ApplicationRecord), no enums, no dependencies.
OPC UA companion specification for the Global Discovery Server — a centralised registry where every OPC UA server in a network registers itself, exposing endpoint URLs, certificates, capabilities. Clients query GDS to discover servers without hardcoding addresses.
What's in the package
| Artefact | Count |
|---|---|
| Enums | — |
| DTOs | 1 |
| Codecs | 1 |
| Registrars | 1 (GdsRegistrar) |
Loading
php
examples/gds/load.php
use PhpOpcua\Client\ClientBuilder;
use PhpOpcua\Nodeset\GDS\GdsRegistrar;
$client = ClientBuilder::create()
->loadGeneratedTypes(new GdsRegistrar())
->connect('opc.tcp://gds.plant.local:4840');
GdsRegistrar is lowercase-d — not GDSRegistrar.
Direct dependencies
None — GDS is a root spec.
Notable types
Types\ApplicationRecordDataType— server registration record. Carries application URI, product URI, application type, server capabilities, discovery URLs. Returned byFindApplicationsand related GDS calls.
Loaded by
- Onboarding — the onboarding flow registers new servers via GDS, so the onboarding spec depends on GDS.
Last updated · 2026-05-25