How can I check the SAP Integration Suite Managed Gateway for Spend&Network standard mappings?

You can check the Standard Mappings in the following path:

1. Access the Integration Portal
2. Resources tab > Implementation Guides > Mapping Specs
3. Expand the Ariba Product Line you use
4. Search for the document type you need to check

When you click on the correspondent document type, a document will be downloaded with all the mappings and fields supported in the SAP Integration Suite, Managed Gateway for Spend Management and SAP Business Network Standard mappings.

SAP Integration Suite Managed Gateway > Managed Gateway - Portal
SAP Integration Suite Managed Gateway > Managed Gateway - Portal > Managed Gateway - Buy Side Mapping tool
SAP Integration Suite Managed Gateway > Managed Gateway for Procurement Custom Map (XSLT)
SAP Integration Suite Managed Gateway > Managed Gateway Foundation & Tools > Managed Gateway for Managed Gateway Portal