Hello @Admin varshini banuri,
welcome to this moderated Azure community forum.
We are not that much in control of securing the inter-module communication using TLS.
These is a section in the local configuration file where you can provide your own TLS certificate.
It has been a while but this is seen in this blog post and I expect this approach is still valid (notice that this is written while the older way of configuration was still in place).
An alternative is checking out the code of the EdgeHub and see for yourself how this is done.
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