Active Object design pattern in physically seperated distributed system

I have a question regarding the Active Object design pattern. It decouples method execution from method invocation. So far so good and in the POSA book of Douglas Schmidt it is presented as concurrency and multi-thread pattern. But the Client and the Active Object is running on the same processor and share same memory.

Now I would like to seperate Client and Active Object, so that they are running on different machines, no sharing of memory. This could a multicomputing system or a web application. How can I achieve that?

I tought, I could maybe replace the Proxy of the Active with a Broker (POSA book) or Gateway (Martin Fowler) but to be honest, I can not tell which approach is the better one or if they are even correct.

Who has an idea for that? Thank you!