The Minimal Lower Layer Protocol (MLLP) protocol is used to transfer HL7 messages. To receive HL7 messages from external sources using MLLP, you enable the MLLP server in your organization. In the MLLP server, you can define how to transfer the message: either through a flat file or through a Kafka queue.
When you receive an HL7 message through the MLLP server, you can write the message to a Kafka queue or to a flat file for further processing. Create the appropriate flat file or Kafka connection and set it as the target type for the MLLP server. Then, to send HL7 messages through MLLP, you can create an MLLP connection and use it as a target in a mapping as part of an outbound flow.
To use MLLP, complete the following tasks:
1. Enable and configure an MLLP server.
To transfer HL7 messages through the MLLP protocol, configure an MLLP server so that partners can connect the server, upload files to the server, and download files from the server.
To enable and configure an MLLP server, use the File Servers page in Administrator. The target type can be a flat file or a Kafka queue. For more information, see File Transfer in the Administrator help.
Note: An MLLP server can transfer only HL7 messages, so the flat files or the Kafka queue must contain HL7 messages.
2. Optionally, create a Kafka connection
Create a Kafka connection in the following scenarios:
- If the MLLP server transfers HL7 messages using a Kafka queue, create a Kafka connection and specify it in the MLLP server properties.
- You want to process HL7 messages using a Kafka queue in a mapping.
3. Optionally, create a flat file connection.
Create a flat file connection if you want to process HL7 messages using a flat file in a mapping.
4. Create an MLLP connection.
An MLLP connection passes the HL7 messages it receives from a third party to the MLLP server.
To create an MLLP connection, use the Connections page in Administrator. For more information about the connection properties, see Connections in the Administrator help.
You can use an MLLP connection only to write HL7 messages to a target in a mapping.
5. Create a mapping.
To process HL7 messages through the MLLP server, create a mapping. In the Source transformation, use the connection that you specified as the target type in the MLLP server. For example, if the target type for the MLLP server is a Kafka queue, then use the Kafka connection in the Source transformation. This mapping will read the HL7 messages that the MLLP server wrote to the Kafka queue and process the messages according to the mapping logic.
Note: When a mapping uses a Kafka queue as a source, the mapping runs in real time and it'll continue running until you stop the job.
To send an HL7 message using MLLP, use the MLLP connection in the Target transformation.
HL7 messages that are transferred through an MLLP server can also generate acknowledgements.