how to to transfer generic OPC data between multiple xa systems in different domain networks
DCOM can be used to make cross domain/workgroup connections, but must be configured correctly (the 800xA Configuration UG gives some advices).
Tunnelers may assist if DCOM access rights should become an obstacle.
Do not use the 800xA service account as it bypasses all security in 800xA.
Upload of entire remote systems is not recommended. Risk of name clashes with undesired effects are high. Regional ABB support can assist to tune upload to avoid this.
I want to add the following;
- Multisystem Integration is a custom made feature that allow a subscriber system to connect to and upload objects and aspects from one or more provider systems. Data access, alarm & event and trend data is supported. Only hierarchical structures are allowed (no bidirectional connections)
- Property Transfer service can be used to transfer a limited number of non-critical properties across two systems; but it is recommended to use regular subscriptions from process graphics, etc before resorting to active property transfer. The destination OPC server is usually the bottle neck/limiting factor in configurations with property transfer. Be sure to find out your destination server's limitations before scaling up the configuration!
- Some OPC tunnelers transform the very much preferred asynchronous access method into the less desirable synchronous method - running subscriptions and writes in parallel over such tunnel may result in disturbances in subscription flow while a write is posted.
- DCOM connections across domains may be eased by implementing "trusts" between the domains.
Don't hesitate to contact your regional ABB sales organization to get help with the design.
Instead of oppening all off xA data to other party via OPC, I would recommend to use one of OPC UA product as a gateway between xA systems.
After transfering one of trust certificate to another, OPC servers can share only desired amound of data to other side. Thanks to trust certificate method that let you get rid of
security and domain or DCOM settings.