Hi Robert,

Welcome to the wolfSSL Forums. Did you init the client structure?

https://github.com/wolfSSL/wolfMQTT/blo … #L211-L213

Could you tell us a bit about your project using wolfMQTT?

Thanks,
Eric - wolfSSL Support

The "100Kb" footprint was achieved with a limited build only supporting pre-shared keys. In order to support certificates for normal TLS, you will need to adjust your footprint expectations. Is PSK a viable path forward for your project?

Hello sasitzar

Welcome to the wolfSSL forums. wolfHSM can utilize wolfCrypt to employ software versions of these PQC algorithms. I'll loop in an engineer for more insights.

Kind regards,
Eric - wolfSSL Support

Hi tritdm

Welcome to the wolfSSL Forums. Could you tell us a bit about you project using wolfMQTT?

It seems like the broker is disconnecting during the TLS handshake? Is this a publicly available broker? You are using a non-standard port. Secure MQTT generally uses port 8883. It may be that the server requires an SNI extension. Here is an example of setting that up:
https://github.com/wolfSSL/wolfMQTT/blo … #L717-L725

Kind regards,
Eric - wolfSSL Support

Also, be sure that `WOLFSSL_DER_TO_PEM` is defined using a CFLAG when configuring wolfSSL:

./configure CFLAGS="-DWOLFSSL_DER_TO_PEM"

Hi Sunnysunday,

I have requested a review of this topic by our engineers.

Thanks,
Eric - wolfSSL Support

Hi Happy,

There could be a configuration issue. `HAVE_CRL` needs to be defined in user_settings.h (or `--enable-crl` if using ./configure).

Share your wolfSSL configuration if the issue persists.

Thanks,
Eric - wolfSSL Support

Yes, the Zephyr port just builds against the main wolfSSL project, so it will be supported.

Hello Anna,

Welcome to the wolfSSL Forums. We do not currently support MLKEM. I would be glad to assist you in making an official feature request. Please send an email to support@wolfssl.com and I will help you get started.

Kind regards,
Eric - wolfSSL Support

Hi iskim,

Welcome to the wolfSSL Forums.

The MQTT protocol uses a keep-alive message called a ping to sustain the communication channel between a client and the broker. During the client connect, the keep_alive_sec field is sent to broker, which uses that to determine if the client has lost it's connection. Some brokers use that value (in seconds) times 1.5 to finally disconnect the client. If your client is not sending the ping (or ping response) within the time frame negotiated, then the broker will disconnect the client.

> - Under what circumstances does WolfMQTT trigger a NETWORK error?

A network timeout can occur when the client attempts to read or write data to the network, but the operation takes too long. This is configurable with the timeout_ms parameter when calling MqttClient_NetConnect.

> - Are there any specific configurations or common pitfalls that I should look into to prevent this kind of disconnection?

A network error might not even be on client side. The application should handle network problems gracefully and allow reconnection attempts.

Could you tell us more about your MQTT project and your location for our support records? Feel free to email us at support@wolfssl.com for a more private conversation.

Kind regards,
Eric - wolfSSL Support

Hi Dwayne,

Thanks for sharing these details. AWS has several requirements for TLS versions and extensions. It might be worthwhile to try updating the wolfSSL version. The latest release is v5.7.2

If this is related to a commercial project, you should open a new issue by emailing support@wolfssl.com or through the zendesk portal at https://wolfssl.zendesk.com.