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Better option is web having reference to wcf directly. As you said, it is good for performance. In case of outsiders, they can come via host.
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Better option is web having reference to wcf directly. As you said, it is good for performance. In case of outsiders, they can come via host.

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you are right, what if creating a project like i mentioned, to have option to go via host (if service later separate from web server). &nbsp;How to achieve that?
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you are right, what if creating a project like i mentioned, to have option to go via host (if service later separate from web server).  How to achieve that?

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I have one issue when creating SOA using wcf. We have web client and other clients (outsider). <br />
<br />
Web -&gt; Host (WCF) -&gt; Service (Contracts) -&gt; Business -&gt; Data -&gt; DB<br />
For web, since it sits in the same web server with the service, instead of calling thru host, i can just directly reference it to service, but then it becomes coupling with service, but advantage will be faster. What do you think? Can I also create a project, where web reference that project. This project basically will either direct me to service directly or can be through host, depends what web tells this project to. Is it also possbile? how to do this?
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I have one issue when creating SOA using wcf. We have web client and other clients (outsider). 

Web -> Host (WCF) -> Service (Contracts) -> Business -> Data -> DB
For web, since it sits in the same web server with the service, instead of calling thru host, i can just directly reference it to service, but then it becomes coupling with service, but advantage will be faster. What do you think? Can I also create a project, where web reference that project. This project basically will either direct me to service directly or can be through host, depends what web tells this project to. Is it also possbile? how to do this?

create service provider to access service either through host or service directly

Windows Communication Foundation (WCF) is a tool used to implement and deploy a service-oriented architecture (SOA) to support distributed computing where services have remote consumers. It features a runtime and a set of APIs in the .NET Framework for building connected, service-oriented applications. Services typically have a WSDL interface (Web Services Description Language) that any WCF client can use to consume the service, regardless of which platform the service is hosted on. WCF implements many advanced Web services (WS) standards such as WS-Addressing, WS-ReliableMessaging, WS-Security, RSS Syndication Services, WS-Discovery, routing and better support for REST services.