WCF service application and wcf service library - wcf

i know it's been asked, but i want to clear things out, what is the difference between WCF service application and wcf service library, and how can i connect them to other machine?
is Wcf SA need to host on IIS? or is it the SL?

A service application includes a website host already setup for you. A service library is a library of services that a host can reference and startup.
If you start with a service library (recommended) you can then choose any host you wish (a windows service, IIS/ASP.NET, or even a console application) and you'd just reference your library from your new host. Choosing a Service Application limits your host to just IIS/ASP.NET (though this might be ok for your purposes, but will limit the protocols you can use).

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Calling a net.tcp wcf service from Silverlight - in an external facing web site?

I have an external (public) website developed in Silverlight. The Silverlight app currently calls http based wcf services hosted in IIS.
I am now having to call a wcf service with net.tcp binding hosted in a different app server. I have the net.tcp wcf service hosted in a windows service on port range 4502-4530 and with an interface to expose clientaccesspolicy.xml file as part of the service. I am able to invoke this service from my Silverlight app in the web server. I want the SL app to make direct call to net.tcp, rather than routing the call to it from another http based service.
Question is will this work without any issues when exposed over internet.
Client browser --> IIS webserver with Silverlight website --> App Server with wcf service on net.tcp.
I am assuming in this case, from XAP SL would try to make direct call to the app server service using net.tcp ?
The communication between the web server and app server could be opened up for ports 4502-4535. But I am wondering what about the client. Does this setup require the ports to be available even in the clients machine (with browser)?
Any insight is much helpful.
Thanks.
Take a look at http://support.microsoft.com/kb/2425652; there is sample code included as well! If you setup clientaccesspolicy.xml correctly; it should work as long as clients can access your TCP server.
If your clients are behind some firewall which is blocking your server's ports; they may face connectivity issues!

Discover locally running WCF from WP7

I have a WCF service running inside Windows Service and it is located on my local network. What I want is to be able to discover WCF from my Silverlight app on my WP7 (on the same network).
I know there a Discovery feature in WCF, however it requires to UDP, which is not supported on WP7. So are there any other ways to discover local WCF?
I also do not know prior to launching WCF the IP address of the WCF service.
The solution I came up with, is to use Sockets as on WP7 they support multicast.
So set up would like this:
Desktop service - Windows Service hosting WCF and small Socket app
which listens on specific port.
WP7 client - before connecting to WCF
a broadcast would be sent using Sockets to find out an IP address of
the machine which runs WCF, when got a response connect to WCF.
For a WCF Service to be referenced in a WP7 project the WCF Service MUST be a BasicEndpoint
You could provide a basic endpoint that exposes a kind of catalog service. It doesn't have to implement UDDI but it could be a custom protocol to suit your needs and return addresses of web services.
This way you only need to know a single address. Of course you can cache returned addresses and query the catalog service only when you are not able to connect.

Questions about adding a WCF service to a Windows service assembly

I have found some basic information about hosting a WCF service in a Windows service, but not much. All of my experience thus far with WCF has been in Web projects. I have a few simple questions.
I have a project which creates a windows service application. I have done a right click -> add WCF Service. This creates Service1.cs and IService1.cs.
I'm wondering why no SVC file is created in this scenario? When I add services to Web projects i get an SVC file which I can navigate to and use to consume the service.
Adding the service adds some configurations to the app.config under the services element. I'm seeing a default base address of
http://localhost:8732/Design_Time_Addresses/WindowsServiceName.services/WCFServiceName/
What does this mean? It's sort of an odd looking address. Am I supposed to change it to whatever I want?
Navigating to this address in a browser results in an unable to connect message. Does the windows service itself have to be running to talk to the WCF service?
How do I go about consuming this service from another application without an svc file?
I'm taking a guess on this first one, but I'm thinking the .svc file when hosting in IIS is to tell IIS, "Hey I have a WCF service here, please handle accordingly".
The base address is as it should be and yes you can change it if I'm not mistaken.
You can't hit the WCF service unless the Windows service is running, which is one of the dangers of hosting in a Windows service, because if the service dies somehow your WCF service is offline until you get the Windows service running again.
You consume the service the same way you do any other WCF service, just using that base address to get at it.

What is the difference between a WCF Service Application and a WCF Service Library?

I am developing a WCF web service and I used the WCF Service Application template to do that.
Does creating a "WCF Service Application" fulfill this requirement?
What are the advantage of creating a WCF Service Library over a WCF Service Application?
A service application includes a website host already setup for you. A service library is a library of services that a host can reference and startup.
If you start with a service library (recommended) you can then choose any host you wish (a windows service, IIS/ASP.NET, or even a console application) and you'd just reference your library from your new host. Choosing a Service Application limits your host to just IIS/ASP.NET (though this might be ok for your purposes, but will limit the protocols you can use).
Edit: Changes in IIS since I wrote this allow for a wider variety of protocols on ASP.NET activated services, so choosing a service application is much less limiting than before.
If all you have is the one project I see only added complexity if you separate for the heck of it. I used a library when I had some particular use cases where I had to host in both a windows service and in IIS.
For IIS you you can move the classes and interfaces to a library but keep your .SVC files in the web project. You must edit the .SVC files to point to the properly qualified classes.

How would you communicate a wcf service with a windows service?

Two weeks ago I needed a way to communicate a wcf service with a windows service running on the same computer. The windows service had to get data from a external source and share it with the wcf service (hosted in IIS) who had to give it when a client made a request. I chose to do that with ipc.
I done it and now the windows service is the ipc server and the wcf service is the ipc client. This goes well but I think I made a mistake doing this because to make it run right the windows service must to be executed with the ASPNET account, for this the ASPNET password account must be assigned and when I do that the IIS does not work correctly.
I am thinking on different alternatives, but in all of them the problem persists. Some ideas?
Edit:
What I needed was a system that made public, in a web service hosted in IIS, data gotten through telnet from another old system, what is a little unstable. How the response of this second system was slow I chose to put a process (the windows service) between the web service and the old system. The windows service had to save the data collected from the old system and when the wcf service asked it give it all at once through ipc.
Why does the windows service need to run as the ASPNET user? Is that because you're using an IPC connection that requires authentication from the caller?
Another alternative (if you have control over the windows-service code) would be to make that a WCF service as well (using a ServiceHost in the windows service). The IIS service could connect to the windows service using a NetTcp or NetNamedPipe binding if you need the IPC-like performance.
Why not just create another account with the same permission set of the ASPNET user which both the WCF service and your other service run under? That way, you have control over the password.
Ideally, the windows service should run as a WCF service, that way its easy for the client to communicate with it.
The next question is weather the 'client' needs to be a WCF service. If this client needs to serve other applications then it is appropriate, otherwise it may not be nessesary. I don't know enough about your system, so its up to you to decide what's best!