java distributed architectures generally use what technology ?

RMI it?
or are there any other techniques ?
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communications Server ?
tcp

distributed server management ?
zk
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communication server .

For example, the system is divided into " user -centric" , "commodity center", which are two separate projects , to be completed by different teams .
now have a new system , you need to use the " user -centric" and "commodity center ", then what kind of a way to interact with it?

I know the way there RMI and Webservice.
java because these systems are developed , so I think it should be better than RMI webservice performance.
I do not know there is no other interactions ?
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1, RPC, which used to be too much trouble to maintain client , Ali dubbo even open source client are saved, and the seamless integration of spring is easy to use , it is recommended
2, webservice, which take up faster and easier

how should I say, feeling a small scale in the system when these two ideas are feasible, is to pay attention when doing architecture on a unified style . After calling the relationship between large-scale subsystems may be more complicated , this time may introduce " service center" , or the MQ, alternative calls between disparate systems with centralized call management. Be it on the evolution of architecture