Enhancing security of communications during execution of protocol flows

A message interface system for a local node supporting communications between the local node and a remote node, the message interface system comprising:

• one or more computer-readable storage mediums storing computer-executable instructions of:
• a broker system, a bridge system, an internal firewall, a secure zone system, and an external firewall, wherein:
• the broker system provides an outbound queue for storing messages received from the local node to be sent to the remote node and an inbound queue for storing messages received from the remote node to be sent to the local node;
• the bridge system subscribes to the outbound queue, initiates a connection through the internal firewall to a reverse proxy server of the secure zone system and a proxy server of the secure zone system, sends through the internal firewall to the reverse proxy server a secure zone signing key, receives outbound messages from the outbound queue, sends the outbound messages through the internal firewall to the proxy server, receives inbound messages through the internal firewall from the reverse proxy server, and sends the inbound messages to the inbound queue;
• and
• the secure zone system comprises the reverse proxy server and the proxy server, wherein
• the reverse proxy server, which stores the secure zone signing key, responds to a connection request received through the external firewall from the remote node using the secure zone signing key, receives inbound messages through the external firewall from the remote node, and sends the inbound messages through the internal firewall to the bridge system, wherein the reverse proxy server does not store state relating to prior inbound messages;
• and
• the proxy server, sends a connection request through the external firewall to the remote node, receives outbound messages through the internal firewall from the bridge system, and sends the outbound messages through the external firewall to the remote node;
• and
• one or more processors for executing the computer-executable instructions stored in the one or more computer-readable storage mediums.