mTLS support with LabVIEW

[Jatin_Verma]

I’m working on a scenario where I need to implement mutual TLS (mTLS) using X.509 certificates over TCP.

My requirement is that both client and server must authenticate each other during the TLS handshake, and the connection must fail if a valid client certificate is not presented.

Specifically, I’m trying to understand:

• Does LabVIEW currently support client certificate authentication?

• Is it possible to enforce mTLS (i.e. reject connections when the client cert is missing or untrusted), rather than it being optional?

The current shipping LabVIEW example shows only one-way authentication.

"C:\Program Files\National Instruments\LabVIEW 2026\examples\Data Communication\Protocols\TLS\TLS Client and Server with Self-Signed Server Certificate.vi"

If anyone has implemented something similar, I would love to connect and talk more about this.

Thanks!
Jatin

[fabznx]

Hi Jatin_Verma,

I am currently working with TLS in LabVIEW.

I just created a small VI to streamline the configuration process.

I assume that mTLS is automatically enabled as soon as 'Add Trusted Certificate To TLS Configuration' is invoked on the server side.

I have yet to test this, but it seems highly likely.

PS: I currently use XCA by Christian Hohnstädt to generate and sign my certificates.

[fabznx]

Well, turns out, it does not work as expected.

Invoking 'Add Trusted Certificate To TLS Configuration' on the server does nothing.

Even invoking 'Add private Key to TLS Configuration' on the client does nothing for 'Accept TLS' on the server-side as the output 'client certificate chain' remains empty.

The fact that there is an error code for this is IMHO a bit confusing.

Error: -715053

The server requires that the client prove its identity with a certificate, but the client is unable to do so.

So far, no solution.