OSI/MHS Orientation Guide

Building Your Message Handling System
OSI/MHS Orientation Guide—424829-001
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What You Need to Do
You can develop both remote and local P7 user agents as EDI applications. The P7
interfaces provide X.435 support as well as support for P0 and P2 methods. With X.435
support, a user agent can submit and retrieve X.435 messages but cannot retrieve
messages based on individual attributes within those messages. With P0 support, EDI
information can be encoded as undefined content of an X.400 message. With the P2
method, EDI information can be encoded as the body part and heading of an
interpersonal message (IPM).
For more information on using the GPI, see “Writing and Integrating Your Own
Messaging System,” earlier in this section. For more information on using remote and
local user agents, respectively, see “Writing and Integrating a Remote User Agent” and
“Writing and Integrating a Local User Agent.”
Whether you write a new EDI application or a program to integrate an existing EDI
application with OSI/MHS, the following are major application planning issues you
must consider:
•
Suitability of your application to an X.400 environment, as opposed to some other
standard environment such as FTAM
•
Whether the application will be continually available to receive messages or,
alternatively, requires a message store
•
Mapping between EDI names and addresses and X.400 names
•
Options for mapping EDI data and delivery specifications to X.400 message formats
and message transfer services, for example:
•
Making the EDI message the content of an X.400 message (the P0 method).
•
Making the EDI message a body part of an interpersonal message (IPM),
extracting information from the EDI message to place in the IPM header
(the P2 method).
•
Use the message format and protocol defined by the X.435 Recommendations
•
Support for any additional X.400 services by the application
These decisions are normally governed by multilateral agreements between trading
partners who communicate across the X.400 network.
Figure 1-11 depicts the three ways of packaging EDI interchanges in X.400 messages.