What are the limitations to this architecture from a technical perspective?
If you observe carefully there is a layer named Webserver IIS and .Net Application Server. Even though the layer can run on 32 bit or 64 bit architecture it uses Microsoft IIS 32 bit architecture. Due to this design the maximum memory is limited to 4GB only, regardless of maximum amount of memory available on RAM. As a result of this large installations with more concurrent users have to use more Web servers with loadbalancing.
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Tags: BPC 7.5 Version for Netweaver Architecture , SAP BPC 7.5 upgrade components, BPC for Basis admins