In-Process Host vs Isolated Host

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The BizTalk Host object represents a logical set of zero or more runtime processes in which you can deploy services, pipelines, and other artifacts. The Host object also represents a collection of runtime instances (zero or more) where the deployed items physically run.

In-process Hosts:It represents what the administrator creates with BizTalk Server Administration Console like orchestration,receive and send port.On The other hand,Isolated Hosts reprensts what the BizTlak Developer creates at runtime like web services and WCF Services.

Recommendation:
It is recommended to build a host for send handelers , a host for receive handlers and a host for processes (orchestrations)
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