[ServiceContract(SessionMode = SessionMode.Required)]
    public interface IServiceTransportModule
    {   [OperationContract]
         bool ValidateAddress(string emailAddress);    
    }

[ServiceBehavior(InstanceContextMode = InstanceContextMode.PerSession)]
    public class TModuleServ : IServiceTransportModule
       { public bool ValidateAddress(string emailAddress)
           {
            string pattern = @"^([0-9a-zA-Z]([-.\w]*[0-9a-zA-Z])*@(([0-9a-zA-Z])+([-\w]*[0-9a-zA-Z])*\.)+[a-zA-Z]{2,9})$";
            return Regex.IsMatch(emailAddress, pattern);
        }
}

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <system.web>
    <identity impersonate="false"/>
    <compilation debug="true" />
    <httpRuntime maxRequestLength="2147483647"
                 executionTimeout="01:00:00"/>
  </system.web>
  <system.serviceModel>
    <diagnostics>
      <messageLogging
        logEntireMessage="true"
        logMalformedMessages="true"
        logMessagesAtServiceLevel="false"
        logMessagesAtTransportLevel="true"
        maxMessagesToLog="2147483647"
        maxSizeOfMessageToLog="2147483647" />
    </diagnostics>
    <bindings>
      <basicHttpBinding>
        <binding name="BasicHttpBinding_IServiceTransportModule" closeTimeout="01:00:00"
          openTimeout="01:00:00" receiveTimeout="01:00:00" sendTimeout="01:00:00"
          hostNameComparisonMode="StrongWildcard" maxBufferSize="2147483647" maxBufferPoolSize="2147483647"
          maxReceivedMessageSize="2147483647" messageEncoding="Text" transferMode="Buffered"
          useDefaultWebProxy="true">
          <readerQuotas maxDepth="2147483647" maxStringContentLength="2147483647"
            maxArrayLength="2147483647" maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
          <security mode="None">
            <transport clientCredentialType="None" />
          </security>
        </binding>
      </basicHttpBinding>
    </bindings>
        <services>
      <service behaviorConfiguration="TransportModuleServiceBehavior"
        name="TransportModuleService.TModuleServ">
        <endpoint address="http://localhost:8080/" binding="basicHttpBinding"
          bindingConfiguration="BasicHttpBinding_IServiceTransportModule"
          name="LOC" bindingName="BasicHttpBinding_IServiceTransportModule"
          contract="TransportModuleService.IServiceTransportModule">                
         <identity>
            <dns value="localhost" />
          </identity>
        </endpoint>
        <endpoint address="http://localhost:8080/mex" binding="mexHttpBinding" name="MM" contract="IMetadataExchange" />
        <host>
          <baseAddresses>
            <add baseAddress="http://localhost:8080/" />
          </baseAddresses>
          <timeouts closeTimeout="01:10:10" openTimeout="01:00:00" />
        </host>
      </service>
    </services>        
    <behaviors>
      <serviceBehaviors>
        <behavior name="TransportModuleServiceBehavior">
          <serviceMetadata httpGetEnabled="True"/>
          <serviceDebug includeExceptionDetailInFaults="False" />
          <dataContractSerializer maxItemsInObjectGraph="2147483647"/>
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>
</configuration>