Inbound and Outbound Web Services
Siebel Business Applications support both inbound and outbound Web services:
Inbound Web services allow external clients to access Siebel functionality. For example, a custom UI that wants to view and modify Siebel service requests.
Outbound Web services allow Siebel Business Applications to make requests of external applications. For example, if the Siebel Server wanted to provide its clients the option of either searching internally or searching the Internet, then the Siebel Server would invoke an Outbound Web service operation against a third-party search engine, incorporating the results in its own reply to the client.
The following image displays Inbound and Outbound Web services.