How to get the Service Identifier/External Identifier used in an ABAP system

The Service Identifier/External Identifier is the business system application ID in an ABAP system,

It is maintained in provider system and used in consumer system.

In consumer system, when create a “System Connection” to provider system, it may popups a dialog to ask the “External Application Key” and user account, like this:

So we need to know how to find this Key in Provider system.

As of SP22 of SAP NetWeaver 7.00, it could be found in SOAMANAGER:

  -> Global System Settings -> Service Identifier (tab):

Then after release 7.30, the path changed to:

-> Technical Administration tab -> SAP Client Settings:

Others, if you are in old release (before 7.00 SP22) or you could not find it, like this:

Then you can use such URL to get the value directly:

http://<host>:<port>/sap/bc/srt/wsil?sap-client=000&List_Biz_Appl_IDs=true

It will show such page:

(Here the EXTERNAL_ID node is what we needed.)