You do not have to set up, configure, and wait for a Web Dispatcher for each system; you use a common Web Dispatcher for all systems. This must then be configured for all connected systems.
SAP Web Dispatcher now serves as the entry point for these systems and performs the following tasks: From the URL the Web Dispatcher identifies the system the request was destined for. The Web Dispatcher then performs load balancing for this system.
You can separate the requests using one of the various mechanisms, or a combination of mechanisms.
Access point (server name/port) of the Web Dispatcher In the Web Dispatcher you can configure an access point for each connected system (combination of host name and port), and forward the requests to the relevant system according to its access point.
URL PrefixYou can define URL prefixes that represent the relationship to the required system. Requests starting with the URL prefix are forwarded to the application servers of this system.
Modified RequestYou can use the modification handler, and define a rule in the Web Dispatcher that specifies the system to which the request is forwarded. To do this, you set the pseudo header field ~webdisp_target_sid.
tags: SAP Web Dispatcher and SSL Server Selection and Load Balancing , sing the SAP Web Dispatcher SAP Web Dispatcher for Multiple Systems Architecture and Functions of the SAP Web Dispatcher Modification of HTTP Requests Metadata Exchange Using SSL High Availability of the SAP Web Dispatcher Processing Administration Requests Memory Requirement of the SAP Web Dispatcher