Introducing...SAP HANA Extended Application Services (XS)
You may have heard of SAP HANA being called a “platform”, or described as a key part of the “Real-Time Data Platform” from SAP. However, for many, SAP HANA equates to a next generation database. Well, SAP HANA is actually all of those things and more. SAP HANA Extended Application Services (just XS for short) is a key aspect of SAP HANA as a platform.
XS is a small-footprint application server, web server, and basis for an application development platform - that lives inside SAP HANA. To be clear, XS is not a completely separate technology that happens to be installed on the same hardware server as SAP HANA; XS is actually an extension of, and tightly integrated into, the SAP HANA Database. SAP began developing XS about three years ago, and there are several applications developed by SAP that are built on XS (one example, SAP Operational Process Intelligence). With the release of SAP HANA SP5, XS became available for customers and partners who wish to develop their own SAP HANA-based applications.
The rationale for XS is mainly twofold: simplicity - enable SAP HANA-based application development and deployment while minimizing architectural layers; and performance - tight integration with the SAP HANA DB ensures optimal performance. With XS, you have the ability to create applications that have an http-based end-user UI (e.g., browser, mobile apps), which run directly on SAP HANA, without additional external servers or system landscape components. This simplified system architecture means low TCO, as complexity of administering or dealing with other heterogeneous components is eliminated. Furthermore, advantages such as efficient inter-process communication taking place inside one overall system, same data types, etc. provide performance advantages that no other application server can match when SAP HANA is the DB.
SAP HANA even includes its own repository for content lifecycle management for all kinds of development artifacts and objects. The scope of applications that can be built using XS is pretty open: it is available for a wide range of application types, from lightweight small web-based applications to more complex enterprise applications. The following diagram describes the basic approach:
Anyone interested in knowing more, or digging deeper, will find Tom Jung’s blog on this topic quite helpful: http://scn.sap.com/community/developer-center/hana/blog/2012/11/29/sap-hana-extended-application-services . Additionally, the development guide for SAP HANA covers XS: http://help.sap.com/hana_appliance > Development Information > SAP HANA Developer Guide.