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You may elect to use a SSH tunnel for secure RPC communication with the node. We also discourage running any software on your CAS server (except for CAS itself) and this includes Bitcoin Core. The solution is use port forwarding to enable access to your separate Bitcoin Core node. We recommend "dialing out" from CAS to the node. See: https://generalbytes.atlassian.net/wiki/spaces/ESD/pages/1002733610/Node+Tutorial+Generic#Port-Forwarding
The general usage would be:
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