web standard protocols.
The XI uses an SAP-specific implementation of the SOAP protocol.
SOAP is a protocol that allows a program running in one system to call a program
running in another system, even when the platforms and technologies of the systems
aredifferent, using XML messaging sent via HTTP. Because it is based on Web
standards (and is itself a web standard), it allows for communication between
applications in an intranet or over the Internet
A SOAP message is sent in the body of an HTTP Post request.
The SOAP protocol requires a SOAP Envelope element as the root element of a
SOAP message. It defines the XML document as a SOAP message. The SOAP
envelope contains an (optional) SOAP Header and a (required) SOAP Body.
The SOAP Header element contains application specific information (like
authentication, payment, etc) about the SOAP message. If the Header element is
present, it must be the first child element of the Envelope element.
The SOAP Body element contains the actual SOAP message intended for the ultimate
endpoint of the message
SAP XI uses an SAP-specific implementation of the SOAP protocol: SOAP with
header extensions and Payload(s). By extending the SOAP standard, XI is able to
enhance the basic capabilities of Web Services to include additional, value-added
functionality.
In this implementation, there are extensions to the basic SOAP Header, such as an
Error Header or Hop List that allow XI to augment the basic functionality offered by
vanilla SOAP systems.
The SOAP body of an XI message contains only a Manifest element, which points to
the actual document being sent.
The Main Payload contains the Business Data that is being sent; there are other
payloads as well, such as a trace document that traces the processing of the
message, and optional payloads for sending additional data (if needed).
The slide shows a sample XI-SOAP message (without the payload). For clarity, the
various header elements (except the Main header) are collapsed.
You can see that the body contains a Manifest element; this in turn contains a Payload
element that has a hyperlink (“href”) to the main document
Technically, an XI message is sent as a multipart-MIME document. MIME is an
internet standard that allows arbitrary digital content to be sent as text over the
internet.
XI Pipeline
XI Messages are passed through a series of processing steps called the XI Pipeline.
An XI pipeline is a configured series of Pipeline Services; A Pipeline Service is an
ABAP Objects class that performs a particular processing step on a message.
All messages that are received at the Integration Server are processed in a consistent
way, with a single set of monitoring and management transactions, regardless of the
underlying platform, technology, or vendor of the application systems involved in the
message exchange.
mySAP applications based on SAP Web Application Server version 6.20 or higher
have their own local instance of the Integration Engine. This allows the application
server to function as a sender or receiver of messages in the native XI-SOAP format
The Pipeline is accessed via a URL, behind which is an ICF service. The URL for
sending a message to the Pipeline is
http://
The
port of the Internet Communication Manager.
Messages are processed through a set of services, each of which performs a specific
operation on the message.
In this way, different configuration steps can be treated as distinct processes. This
provides for the maximum flexibility and maximum reusability of objects.
Adapter Engine
The Adapter Engine provides connectivity to the XI for non-Web AS Interfaces (3rd
party systems).
The Adapter Engine has built in capabilities for message queueing, tracing, logging. It
uses a different runtime mechanism for sending message than an Integration Server;
in other words, the adapter engine can formulate and send an XI-SOAP message
without requiring an integration engine.
