Administration of Standalone Engines 
This section contains the administration tasks for additional installable entities that function “standalone”, and which are not really SAP NetWeaver systems.
They provide a specific server function in combination with one or more usage types:
● Search and Classification (TREX)
TREX offers SAP applications services for search and classification of large collections of documents and for searching and aggregating business objects.
SAP liveCache technology is a database engine for managing complex objects in SAP solutions such as Supply Chain Management (Advance Planner and Optimizer) and Product Lifecycle Management.
● RTC Application Sharing Server
Dedicated server for application sharing processes and data streaming on the Portal.
● Precalculation Server (BI)
The precalculation server allows the BEx Analyzer to precalculate workbooks, which can be distributed to other users in the context of Information Broadcasting. For more information, see Microsoft Excel Integration.
The SAP Content Server is a stand-alone component in which a large quantity of electronic documents of any format and with any content can be stored.
● SAP NetWeaver Landscape-Wide Job Scheduler
As of SAP NetWeaver ’04, there is a Job Scheduler available for landscape-wide background processing in addition to the traditional local SAP background processing (transactions SM36/SM37).
The SAP Web dispatcher lies between the Internet and your SAP system. It is the entry point for HTTP(s) requests into your system, which consists of one or more Web application servers. As a "software web switch", the SAP Web dispatcher can reject or accept connections. When it accepts a connection, it balances the load to ensure an even distribution across the servers.
If you want to guarantee high availability for your SAP system from all the software and hardware components you are using, you will benefit from using the standalone enqueue. The use of the standalone enqueue server means that the crucial component (enqueue server with lock table) is kept as small as possible. Instead of the classical central instance in your system (entire application server with enqueue work process and lock table – usually the message server also runs on this server), you have one slim line central instance consisting of the enqueue server and the message server only. It is far easier to make this one central instance a high availability (HA) solution.