Hi,
I have never been using Active Transfer, but I will try to answer for the other components:
Usually you would require at least one instance for messaging (UM in your question) and one instance for MWS and CommandCentral if you plan to use Landscape Management.
For IS this will depend on the number of packages, the number of nodes in the packages and the size of the documents being processed.
It is possible to have different (unclustered) instances of IS (each having its own db schema) when your processing can be decoupled by using publish/subscribe via messaging and a shared doc type.
Certain features cannot be shared across instances, i.e. TaskEngine in MWS.
This one can only work with dedicated IS instances, it is not possible to have one TaskEngine MWS running Tasks processes in different IS instances.
Regards,
Holger
#webMethods#BPM#Universal-Messaging-Broker#MWS-CAF-Task-Engine#Application-Platform#Integration-Server-and-ESB#webMethods-io-Integration