The GateKeeper is a plug-in that checks incoming messages to see if they are welcome. For this purpose, a list is created for each server port to be protected, which messages are allowed.
The list is an XML file ("gatekeeper. xml") and is located in the configuration directory of each NODES. It looks like this:
Messages can be scanned for specific combinations of record IDs, namespaces and NODE IDs. Listed messages are let into the system. Messages that are not listed are rejected and logged. These messages are sent back to the sender with an error code.