How To Set Up the Write/Read Endpoint URLs for LabVIEW Network Streams That Support Multiple Host Applications With One Real-Time Target Application?

Updated Mar 24, 2025

Environment

Software

  • LabVIEW

Other

I have a customer who uses PXI Real-Time target with the host system when he sets up the network stream in the Labview development environment, everything works fine. When he generated the VIs into applications and found out that only one application could communicate with the target application simultaneously, the other application would not respond and report an error. He wondered why and how to fix the issue.  

Something about Network Stream Endpoint URLs

  • ni.dex is the protocol of the URL and is optional.  If you do not specify ni.dex with the create functions, LabVIEW will infer this protocol.
  • host_name is the project alias, DNS name, or IP address of the computer on which the endpoint resides.  In addition, the string “localhost” can be used as a pseudonym for the computer on which the code is currently executing.  If host_name is left blank, localhost is inferred.  LabVIEW searches for a matching hostname in the following order: Project alias, DNS name, and then IP address.
  • context_name is the name that identifies which application context the endpoint resides in.  This is only necessary if the network streams feature is being used by multiple application instances on the same computer.  By default, the context name is an empty string and all endpoints are created in the default context.  When using the default context, you can omit the colon separator.   
  • endpoint_name is the actual name of the stream endpoint.  This name can be a flat string or a hierarchical path of strings separated by the forward slash character.  For example, stream 1 or Subsystem A/stream 1.

 Step 1 : Set up the unique identification of the names in target VI as follows

So you will be able to get the read names for the target that can communicate the first application in the host. <You will set up and send the variable context to the first host application.> The variable Context will look like Read/Arb684

You will repeat the process for the endpoint you want to specify, in this case, two similar target read endpoints will be created using the name methodology.

Step 2:  Send the shared variable to pass the identification to the host

The URL you specified here will be like //10.144.130.151/Read/Arb684 <The IP address is the target IP, and the string after it is coming from the shared variable you passed from the target application>

Step 3 : Set up the communication for the host application as above and you will able to realize the function for two different applications communicate and stream with the target applications at the same time.

The test result is as follows