jmcfet

for a wonderful and simple (I like simple ) see Jeff Prosise's article http://www.wintellect.com/CS/blogs/jprosise/archive/2009/08/27/silverlight-3-s-new-and-improved-duplex-networking-clients.aspx

This really helped me as we needed more like Jeff is doing as we wanted our SL UI to repond to server progress events and the duplexMode="MultipleMessagesPerPoll" was causing my responses to be buffered so it looked like they were not working. Looking at Jeffs example cleared the air. It worked fine after converting project to SL4

thanks  to this great post  http://ajdotnet.wordpress.com/2010/08/08/silverlight-and-integrated-authentication/#comment-8636  I kind of solved the problem by  removing MEX endpoint  But this seems like a bug me as MEX should only be used in discovery. The really wierd part is that after I remove the MEX endpoint and disable anonymous auth for the service I can still update my service from the SL client. Go fiqure something is not good here

I followed your excellent video and build a sample using http://msdn.microsoft.com/en-us/library/cc645027(v=vs.95).aspx">http://msdn.microsoft.com/en-us/library/cc645027(v=vs.95).aspx and thanks to both sources
thing looked great till we turned on Windows authentication"  and turned off "allow anonymous authentication" on the service using IIS console. We
have alot of security minded clients and the thought of enabling
this makes them run for the hills! I know that this should not present a security issue as the service will use Windows auth
but the client is always right. When we do this we get the following error:

Exception: System.ServiceModel.ServiceActivationException: The service '/DuplexService1/Service1.svc' cannot be activated
due to an exception during compilation.  The exception message is: Security settings for this service require 'Anonymous'
 Authentication but it is not enabled for the IIS application that hosts this service.. ---> System.NotSupportedException: Security
settings for this service require 'Anonymous' Authentication but it is not enabled for the IIS application that hosts this service.

Now we also tried building a CustomBinding

<system.serviceModel>
    <!-- Register the binding extension from the SDK. -->
    <extensions>
      <bindingElementExtensions>
        <add name="pollingDuplex" type="System.ServiceModel.Configuration.PollingDuplexElement, System.ServiceModel.PollingDuplex"/>
      </bindingElementExtensions>
      <bindingExtensions>
                <add name="pollingDuplexHttpBinding" type="System.ServiceModel.Configuration.PollingDuplexHttpBindingCollectionElement,System.ServiceModel.PollingDuplex, Version=4.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" />
      </bindingExtensions>
    </extensions>
    <!-- Create the polling duplex binding. -->
    <bindings>
       <customBinding>
        <binding name="pollingBindingConfig" closeTimeout="00:01:05" openTimeout="00:01:05" receiveTimeout="00:01:10" sendTimeout="00:01:10">
          <binaryMessageEncoding maxReadPoolSize="64" maxWritePoolSize="16"
            maxSessionSize="2048">
            <readerQuotas maxDepth="32" maxStringContentLength="8192" maxArrayLength="16384"
              maxBytesPerRead="4096" maxNameTableCharCount="16384" />
          </binaryMessageEncoding>
          <pollingDuplex maxPendingSessions="2147483647"
                         maxPendingMessagesPerSession="2147483647" />

          <httpTransport manualAddressing="false" maxBufferPoolSize="524288"
            maxReceivedMessageSize="65536" allowCookies="false" authenticationScheme="Negotiate"
            bypassProxyOnLocal="false" hostNameComparisonMode="StrongWildcard"
            keepAliveEnabled="true" maxBufferSize="65536" proxyAuthenticationScheme="Negotiate"
            realm="" transferMode="Buffered" unsafeConnectionNtlmAuthentication="false"
            useDefaultWebProxy="true" />
        </binding>
      </customBinding>

    </bindings>

    <behaviors>
      <serviceBehaviors>
        <behavior>
          <!-- To avoid disclosing metadata information, set the value below to false and remove the metadata endpoint above before deployment -->
          <serviceMetadata httpGetEnabled="true" />
          <!-- To receive exception details in faults for debugging purposes, set the value below to true.  Set to false before deployment to avoid disclosing exception information -->
          <serviceDebug includeExceptionDetailInFaults="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
    <services>
      <service name="DuplexService1.OrderService">

        <!-- Service Endpoints -->
        <endpoint address="" binding="customBinding"  bindingConfiguration="pollingBindingConfig" contract="DuplexService1.IDuplexService">
        </endpoint>
        <endpoint address="mex" binding="mexHttpBinding" contract="IMetadataExchange" />
      </service>
    </services>

again the same result. The other curious thing is the that the SL ClientConfig file is always empty.(<configuration />. Surely SL Duplex communications does not
require Anonymous auth to be on or we are up the creek.