http://scn.sap.com/community/crm/blog/2013/06/10/global-data-context-parametersgdc
https://wiki.scn.sap.com/wiki/display/CRM/SAP+CRM+WEB+UI+How+Global+Data+Context+Works
HI,
Once you have confirmed the customer , the data is loaded in the GDC(Global data Context).
You can read the customer from GDC using Parameter CURRENTCUSTOMER.
So that when Service Request is being created, BP can be read and pre-populated.
Check the links to understand how GDC works and can be used.
Thanks
Deepak