ABAP ARCITECTURE
ABAP ARCITECTURE environments communicate directly via the SAP Java Connector (JCo). AS ABAP Architecture In AS ABAP, the central instance is distinguished by the fact that the message server and the enqueue work process run there. All other instances of the system are usually called dialog instances. Alternatively, the instances are also named after the services provided. The services that an application server can provide are determined by the type of work processes it has. An application server can then take on several roles, for example, as a dialog server and simultaneously as an update server, if it provides several dialog work processes and at least one update work process. Note: An overview of the AS ABAP instances is available in SM51 (in SAP Easy Access under Tools → Administration → Monitor → System Monitoring→ Servers. You can use the transaction SM50 to display an overview of the work processes on the instance that you are logged on to; you can also display this over