Discovery Usecase

Unified Architecture topics related to OPC UA Specification, compliant behavior and any technical issues of OPC UA, like Security, Information Model, Companion Specs DI, PLCopen, ADI, ...

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Discovery Usecase

Post by rakshan »

I have a question on Discovery.
Suppose a network has multiple client and servers. A client wants to establish connection to the serverA. However, that serverA is already having a session with other clientB.
Theory says servers can have multiple sessions with multiple clients. I am curious if there is any approach where in, when the client tries to reach to serverA, it gets a response saying its busy and not available(considering only 1 session could be established by a client and server).

REST API could be one of the approaches with sessionless data transfer. Or any other approach you suggest?


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Re: Discovery Usecase

Post by Support Team »


it for sure makes no sense to add a REST API to OPC UA.
Generally any UA Server is always capable of handling multiple connections simultaniously, typically at least 2 but up to 50 or even 100. If the maximum limit is exceeded the next Client can not establish another connection (returns error on connection attempt).

There is no reason to have an extra API for that, it just don't work.
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Unified Automation Support Team

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