I've set up MQTT on AWS and mosquitto on my local machine.
I can connect to AWS using CA root file, client certificate file and client key file on port 8883.
I hoping to be able to connect via port 1883 on MQTT without initiating the connection via TLS (a.k.a. not on MQTTS). Is this possible using AWS?
No, because the SSL is doing more than just encrypting the connection, it is also authenticating the client using the client side certificate and private key.
If you were to use unencrypted MQTT and pass a username and password then those values world be transmitted in the clear so potentially subject to interception.
