1. AddressSpace Hierarchy

Root Node:

• Objects/NG-Gateway

Hierarchy Structure:

• Objects/NG-Gateway/{channel}/{device}/{point}

Where:

• {channel} uses channel_name as browse name
• {device} uses device_name
• {point} uses point_key

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2. NodeId Rules

Each point Variable uses String NodeId:

ns=1;s={channel}.{device}.{point_key}

Each component will be sanitized:

• Allowed: [A-Za-z0-9._-]
• Other characters replaced by -

Important: Do not change sanitize strategy arbitrarily

Once changed, NodeId/mapping saved on client side will become invalid (Breaking change).

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3. DataType and AccessLevel Mapping

• Variable DataType mapped from point data_type
• AccessLevel mapped from point access_mode:
  • Read → CURRENT_READ
  • Write → CURRENT_WRITE
  • ReadWrite → READ|WRITE

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4. Expose "Subscribed Points" Only

Current implementation intentionally avoids "Exposing all gateway points":

• Nodes are created on demand when processing Telemetry/Attributes (lazy)
• Runtime delta (Point add/delete/modify) only updates "Points already existing in local cache"

This means:

• Unsubscribed/Unrouted data points will not suddenly appear in OPC UA Server
• You need to create AppSubscription first and ensure data enters this App