diff --git a/ZeroLevel.UnitTests/ExchangeTests.cs b/ZeroLevel.UnitTests/ExchangeTests.cs
new file mode 100644
index 0000000..0bd9044
--- /dev/null
+++ b/ZeroLevel.UnitTests/ExchangeTests.cs
@@ -0,0 +1,99 @@
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
+using ZeroLevel.Network;
+
+namespace ZeroLevel.NetworkUnitTests
+{
+    [TestClass]
+    public class ExchangeTests
+    {
+        [TestMethod]
+        public void HandleMessageTest()
+        {
+            // Arrange
+            var info = new ExServiceInfo
+            {
+                Endpoint = "192.168.1.11:7755",
+                ServiceGroup = "MyServiceGroup",
+                ServiceKey = "MyServiceKey",
+                ServiceType = "MyServiceType",
+                Version = "1.1.1.1"
+            };
+            var locker = new ManualResetEvent(false);
+            var server = ExchangeTransportFactory.GetServer(6666);
+            ExServiceInfo received = null;
+
+            server.RegisterInbox<ExServiceInfo>("register", (i, _, __) =>
+            {
+                received = i;
+                locker.Set();
+            });
+
+            // Act
+            var client = ExchangeTransportFactory.GetClient(server.Endpoint.Address.ToString() + ":6666");
+            var ir = client.Send<ExServiceInfo>("register", info);
+
+            locker.WaitOne(1000);
+
+            // Assert
+            Assert.IsTrue(ir.Success);
+            Assert.IsTrue(info.Equals(received));
+
+            // Dispose
+            locker.Dispose();
+            client.Dispose();
+            server.Dispose();
+        }
+
+        [TestMethod]
+        public void RequestMessageTest()
+        {
+            // Arrange
+            var info1 = new ExServiceInfo
+            {
+                Endpoint = "192.168.1.11:7755",
+                ServiceGroup = "MyServiceGroup",
+                ServiceKey = "MyServiceKey",
+                ServiceType = "MyServiceType",
+                Version = "1.1.1.1"
+            };
+            var info2 = new ExServiceInfo
+            {
+                Endpoint = "192.168.41.11:4564",
+                ServiceGroup = "MyServiceGroup",
+                ServiceKey = "MyServiceKey2",
+                ServiceType = "MyServiceType",
+                Version = "1.1.0.1"
+            };
+            var locker = new ManualResetEvent(false);
+            var server = ExchangeTransportFactory.GetServer(6666);
+            IEnumerable<ExServiceInfo> received = null;
+
+            server.RegisterInbox<IEnumerable<ExServiceInfo>>("services", (_, __) => new[] { info1, info2 });
+
+            // Act
+            var client = ExchangeTransportFactory.GetClient(server.Endpoint.Address.ToString() + ":6666");
+            var ir = client.Request<IEnumerable<ExServiceInfo>>("services", response =>
+            {
+                received = response;
+                locker.Set();
+            });
+
+            locker.WaitOne(1000);
+
+            // Assert
+            Assert.IsTrue(ir.Success);
+            Assert.IsTrue(CollectionComparsionExtensions.OrderingEquals(new[] { info1, info2 }, received, (a, b) => a.Equals(b)));
+
+            // Dispose
+            locker.Dispose();
+            client.Dispose();
+            server.Dispose();
+        }
+    }
+}
diff --git a/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj b/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
index c4739c4..8e255e4 100644
--- a/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
+++ b/ZeroLevel.UnitTests/ZeroLevel.UnitTests.csproj
@@ -51,6 +51,7 @@
   <ItemGroup>
     <Compile Include="ArrayToolsTest.cs" />
     <Compile Include="CollectionsTests.cs" />
+    <Compile Include="ExchangeTests.cs" />
     <Compile Include="InvokingTest.cs" />
     <Compile Include="MappingTest.cs" />
     <Compile Include="Models\BaseClass.cs" />
diff --git a/ZeroLevel/Services/Network/Services/DiscoveryClient.cs b/ZeroLevel/Services/Network/Services/DiscoveryClient.cs
index 0562cc7..dc6833a 100644
--- a/ZeroLevel/Services/Network/Services/DiscoveryClient.cs
+++ b/ZeroLevel/Services/Network/Services/DiscoveryClient.cs
@@ -70,7 +70,7 @@ namespace ZeroLevel.Network
 
         public IEnumerable<ServiceEndpointInfo> GetServiceEndpoints(string serviceKey)
         {
-            var key = serviceKey.Trim().ToLowerInvariant();
+            var key = serviceKey.Trim().ToUpperInvariant();
             _lock.EnterReadLock();
             try
             {
@@ -88,7 +88,7 @@ namespace ZeroLevel.Network
 
         public IEnumerable<ServiceEndpointInfo> GetServiceEndpointsByGroup(string serviceGroup)
         {
-            var group = serviceGroup.Trim().ToLowerInvariant();
+            var group = serviceGroup.Trim().ToUpperInvariant();
             _lock.EnterReadLock();
             try
             {
@@ -106,7 +106,7 @@ namespace ZeroLevel.Network
 
         public IEnumerable<ServiceEndpointInfo> GetServiceEndpointsByType(string serviceType)
         {
-            var type = serviceType.Trim().ToLowerInvariant();
+            var type = serviceType.Trim().ToUpperInvariant();
             _lock.EnterReadLock();
             try
             {
diff --git a/ZeroLevel/Services/Serialization/PrimitiveTypeSerializer.cs b/ZeroLevel/Services/Serialization/PrimitiveTypeSerializer.cs
index 94f2c07..ae2f4ae 100644
--- a/ZeroLevel/Services/Serialization/PrimitiveTypeSerializer.cs
+++ b/ZeroLevel/Services/Serialization/PrimitiveTypeSerializer.cs
@@ -282,17 +282,25 @@ namespace ZeroLevel.Services.Serialization
                         }
                         else if (TypeHelpers.IsAssignableToGenericType(type, typeof(IEnumerable<>)))
                         {
-                            var typeArg = type.GetGenericArguments().First();
-                            if (_enumTypesCachee.ContainsKey(typeArg))
+                            Type elementType;
+                            if (TypeHelpers.IsArray(type))
                             {
-                                _concrete_type_cachee[type] = _cachee[_enumTypesCachee[typeArg]];
+                                elementType = type.GetElementType();
                             }
-                            else if (typeof(IBinarySerializable).IsAssignableFrom(typeArg))
+                            else
+                            {
+                                elementType = type.GetGenericArguments().First();
+                            }
+                            if (_enumTypesCachee.ContainsKey(elementType))
+                            {
+                                _concrete_type_cachee[type] = _cachee[_enumTypesCachee[elementType]];
+                            }
+                            else if (typeof(IBinarySerializable).IsAssignableFrom(elementType))
                             {
                                 var wrapper = new Wrapper { Invoker = InvokeWrapper.Create() };
 
-                                wrapper.ReadId = wrapper.Invoker.ConfigureGeneric(typeof(MemoryStreamReader), typeArg, "ReadCollection").First();
-                                wrapper.WriteId = wrapper.Invoker.ConfigureGeneric(typeof(MemoryStreamWriter), typeArg,
+                                wrapper.ReadId = wrapper.Invoker.ConfigureGeneric(typeof(MemoryStreamReader), elementType, "ReadCollection").First();
+                                wrapper.WriteId = wrapper.Invoker.ConfigureGeneric(typeof(MemoryStreamWriter), elementType,
                                         mi => mi.Name.Equals("WriteCollection") && mi.IsGenericMethod).First();
                                 _concrete_type_cachee[type] = wrapper;
                             }