This is an important and critical topic, and there are not many documentations out there.
I am trying to connect SIM868 to my google IoT core, and I am able to send the CONNECT packet which is recognized by the IoT core, but the connection is closed immediately after.
But I skipped one step included on GCP IoT: https://cloud.google.com/iot/docs/how-tos/mqtt-bridge#downloading_mqtt_server_certificates
They say you need to " Downloading MQTT server certificates" onto your device for the IoT core to allow the communication. I thought that by simply having the CIPSSL=1 would work, but it doesn’t.
I did follow the instructions on the SIM800 Series SSL and FS document about assigning a SSL certificate, which goes as follows:
Create certificate file on FS.
AT+FSWRITE=C:\USER\HENRY_SSL.CRT,0,1196,10 > OK
Write file to FS.
AT+SSLSETCERT=“C:\USER\HENRY_SSL.CRT”,"********" OK +SSLSETCERT: 0
Import certificate file Import succeed
However, the AT+SSLSETCERT step it always returns 1. I am not sure what the password should be. Or what is that I am doing wrong. I assigned the .cert file both insise the /user and also outside directory, still no luck.
@RaviPujar I saw on another post that you were attempting this. Any luck?
Anyone else on the community?