PO Transfer Vendor in SRM

Question

Requirement:
I have a requirement to restrict the PO sending for a specific vendor (External), during PO amendment in SRM system.
SAP ---> XI ---> Vendor system.
What I did:
I was trying to use the method of copying the implementation BBP_PO_SEND_XML to a user-defined implementation ‘ZBBP_PO_SEND_XML’ (referring the note 492988).
My query:
1. In one of the blog I read " If you don't activate XI in the customizing, then SRM considers the BC scenario during the PO XML output ". Where do i need to set this?
Is there any specific setting in SPRO for XI activation?
2. During the PO sending none of the functions mentioned below is getting triggered:
a. BCEBPXML1 BBP_BAPI_PO_SEND
b. XIEBPXML1 BBP_XI_PO_SEND
c.  XISAPXML1 BBP_SAPXML1_PO_SEND.
Is the triggering of the FM's are scenario specific?
3. Can anyone suggest a solution for my requirement?
Kindly advice me how to proceed.
Warm Regards,
Jojo

Answer 1

Hello Jojo,
There is a specific setting that needs to be active  if you want to use XI as an XML interface.
Go to Customizing>SRM> SRM Server -->Cross Application Basic Settings --> Enable use of Exchange Infrastructure.
for example: Enable Use of Exchange Infrastructure
Use
Here you determine if Enterprise Buyer is to use the Exchange Infrastructure for communication between system components.
Activities
To enable the Exchange Infrastructure for your system, flag the indicator Use Application Infrastucture. The system then exchanges data between system components via interfaces of the Exchange Infrastructure.
Example
Within SRM scenarios, for example, Supplier Self-Services (SUS), you exchange documents between Enterprise Buyer and a SUS System
with regards,
mahesh