Enterprise Systems - Revisited
	Rainer Brendle, SAP

	For many years, SAP's Enterprise Applications have delivered
highest throughput and availability required by our customers. Like any
systems vendor, SAP needs to respond to technical and business forces
that are reshaping the industry, some of which also were described by
Pat Helland at HPTS 2007. The forces include hardware trends, cloud
computing and user experience expectations emerging from consumer apps.
Main memory sizes and costs enable use of distributed clouds of main
memory datastores for high performance. Clouds out-source IT and provide
on-demand elastic resourcing. Users expect more responsive interaction
channels offering flexible access to data and businesses processes. It
is important to revisit architectures for Enterprise Applications and
Systems to determine where changes are needed, and to explore options
for change.

	We describe an experimental architecture for Enterprise
Application Systems based on a distributed cloud of servers using
asynchronous message-passing, event-driven programming, and a
transactional business event datastore in-memory and on disk. This model
is very well suited and tested for enterprise applications. It can
provide the needed transactional consistency and scalability for
enterprise applications in a distributed environment. The distributed
in-memory datastores can be optimized for various data access patterns
including business transactions, analytics and search.