If many messages are irrelevant to you then you can choose to ignore them. While you do have to make a functional HL7 acknowledgment for each message you receive, this can be quite easily achieved using Auto Acknowledgements. Messages you are not interested in can be filtered by setting up a Default Message. This default message event will be fired every time a message is received that does not match any other message defined in the message definition file. You can then choose to do anything you like with those messages such as logging them into a file.