Merge github.com:grpc/grpc into cleaner-posix2

54 files changed, 580 insertions, 201 deletions

diff --git a/Makefile b/Makefile
index 758690bd29..2d46699d81 100644
--- a/Makefile
+++ b/Makefile
@@ -3164,6 +3164,7 @@ LIBGRPC++_TEST_UTIL_SRC = \
     test/cpp/util/create_test_channel.cc \
     test/cpp/util/string_ref_helper.cc \
     test/cpp/util/subprocess.cc \
+    test/cpp/util/test_credentials_provider.cc \
 
 
 LIBGRPC++_TEST_UTIL_OBJS = $(addprefix $(OBJDIR)/$(CONFIG)/, $(addsuffix .o, $(basename $(LIBGRPC++_TEST_UTIL_SRC))))
@@ -3214,6 +3215,7 @@ $(OBJDIR)/$(CONFIG)/test/cpp/util/cli_call.o: $(GENDIR)/src/proto/grpc/testing/e
 $(OBJDIR)/$(CONFIG)/test/cpp/util/create_test_channel.o: $(GENDIR)/src/proto/grpc/testing/echo_messages.pb.cc $(GENDIR)/src/proto/grpc/testing/echo_messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.grpc.pb.cc
 $(OBJDIR)/$(CONFIG)/test/cpp/util/string_ref_helper.o: $(GENDIR)/src/proto/grpc/testing/echo_messages.pb.cc $(GENDIR)/src/proto/grpc/testing/echo_messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.grpc.pb.cc
 $(OBJDIR)/$(CONFIG)/test/cpp/util/subprocess.o: $(GENDIR)/src/proto/grpc/testing/echo_messages.pb.cc $(GENDIR)/src/proto/grpc/testing/echo_messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.grpc.pb.cc
+$(OBJDIR)/$(CONFIG)/test/cpp/util/test_credentials_provider.o: $(GENDIR)/src/proto/grpc/testing/echo_messages.pb.cc $(GENDIR)/src/proto/grpc/testing/echo_messages.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.pb.cc $(GENDIR)/src/proto/grpc/testing/echo.grpc.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.pb.cc $(GENDIR)/src/proto/grpc/testing/duplicate/echo_duplicate.grpc.pb.cc
 
 
 LIBGRPC++_UNSECURE_SRC = \
@@ -13017,6 +13019,7 @@ test/cpp/util/create_test_channel.cc: $(OPENSSL_DEP)
 test/cpp/util/string_ref_helper.cc: $(OPENSSL_DEP)
 test/cpp/util/subprocess.cc: $(OPENSSL_DEP)
 test/cpp/util/test_config.cc: $(OPENSSL_DEP)
+test/cpp/util/test_credentials_provider.cc: $(OPENSSL_DEP)
 endif
 
 .PHONY: all strip tools dep_error openssl_dep_error openssl_dep_message git_update stop buildtests buildtests_c buildtests_cxx test test_c test_cxx install install_c install_cxx install-headers install-headers_c install-headers_cxx install-shared install-shared_c install-shared_cxx install-static install-static_c install-static_cxx strip strip-shared strip-static strip_c strip-shared_c strip-static_c strip_cxx strip-shared_cxx strip-static_cxx dep_c dep_cxx bins_dep_c bins_dep_cxx clean
diff --git a/build.yaml b/build.yaml
index e59bd8e733..acbc8de4ea 100644
--- a/build.yaml
+++ b/build.yaml
@@ -717,6 +717,7 @@ libs:
   - test/cpp/util/create_test_channel.h
   - test/cpp/util/string_ref_helper.h
   - test/cpp/util/subprocess.h
+  - test/cpp/util/test_credentials_provider.h
   src:
   - src/proto/grpc/testing/echo_messages.proto
   - src/proto/grpc/testing/echo.proto
@@ -727,6 +728,7 @@ libs:
   - test/cpp/util/create_test_channel.cc
   - test/cpp/util/string_ref_helper.cc
   - test/cpp/util/subprocess.cc
+  - test/cpp/util/test_credentials_provider.cc
   deps:
   - grpc++
   - grpc_test_util
diff --git a/doc/load-balancing.md b/doc/load-balancing.md
new file mode 100644
index 0000000000..681be02a72
--- /dev/null
+++ b/doc/load-balancing.md
@@ -0,0 +1,97 @@
+Load Balancing in gRPC
+=======================
+
+# Objective
+
+To design a load balancing API between a gRPC client and a Load Balancer to
+instruct the client how to send load to multiple backend servers. 
+
+# Background
+
+Prior to any gRPC specifics, we explore some usual ways to approach load
+balancing.
+
+### Proxy Model
+
+Using a proxy provides a solid trustable client that can report load to the load
+balancing system. Proxies typically require more resources to operate since they
+have temporary copies of the RPC request and response. This model also increases
+latency to the RPCs.
+
+The proxy model was deemed inefficient when considering request heavy services
+like storage. 
+
+### Balancing-aware Client
+
+This thicker client places more of the load balancing logic in the client. For
+example, the client could contain many load balancing policies (Round Robin,
+Random, etc) used to select servers from a list. In this model, a list of
+servers would be either statically configured in the client, provided by the
+name resolution system, an external load balancer, etc. In any case, the client
+is responsible for choosing the preferred server from the list. 
+
+One of the drawbacks of this approach is writing and maintaining the load
+balancing policies in multiple languages and/or versions of the clients. These
+policies can be fairly complicated. Some of the algorithms also require client
+to server communication so the client would need to get thicker to support
+additional RPCs to get health or load information in addition to sending RPCs
+for user requests.
+
+It would also significantly complicate the client's code: the new design hides
+the load balancing complexity of multiple layers and presents it as a simple
+list of servers to the client.
+
+### External Load Balancing Service
+
+The client load balancing code is kept simple and portable, implementing
+well-known algorithms (ie, Round Robin) for server selection.
+Complex load balancing algorithms are instead provided by the load balancer. The
+client relies on the load balancer to provide _load balancing configuration_ and
+_the list of servers_ to which the client should send requests. The balancer
+updates the server list as needed to balance the load as well as handle server
+unavailability or health issues. The load balancer will make any necessary
+complex decisions and inform the client. The load balancer may communicate with
+the backend servers to collect load and health information.
+
+# Proposed Architecture
+
+The gRPC load balancing approach follows the third approach, by having an
+external load balancer which provides simple clients with a list of servers.
+
+## Client
+
+When establishing a gRPC stream to the balancer, the client will send an initial
+request to the load balancer (via a regular gRPC message). The load balancer
+will respond with client config (including, for example, settings for flow
+control, RPC deadlines, etc.) or a redirect to another load balancer. If the
+balancer did not redirect the client, it will then send a list of servers to the
+client. The client will contain simple load balancing logic for choosing the
+next server when it needs to send a request.
+
+## Load Balancer
+
+The Load Balancer is responsible for providing the client with a list of servers
+and client RPC parameters. The balancer chooses when to update the list of
+servers and can decide whether to provide a complete list, a subset, or a
+specific list of “picked” servers in a particular order. The balancer can
+optionally provide an expiration interval after which the server list should no
+longer be trusted and should be updated by the balancer.
+
+The load balancer may open reporting streams to each server contained in the
+server list. These streams are primarily used for load reporting. For example,
+Weighted Round Robin requires that the servers report utilization to the load
+balancer in order to compute the next list of servers.
+
+## Server
+
+The gRPC Server is responsible for answering RPC requests and providing
+responses to the client. The server will also report load to the load balancer
+if a reporting stream was opened for this purpose.
+
+### Security 
+
+The load balancer may be separate from the actual server backends and a
+compromise of the load balancer should only lead to a compromise of the
+loadbalancing functionality. In other words, a compromised load balancer should
+not be able to cause a client to trust a (potentially malicious) backend server
+any more than in a comparable situation without loadbalancing. 
diff --git a/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs b/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
index f77e9c6573..1837f5c74b 100644
--- a/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
+++ b/src/csharp/Grpc.Auth/GoogleAuthInterceptors.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -71,7 +71,7 @@ namespace Grpc.Auth
         /// <returns>The interceptor.</returns>
         public static AsyncAuthInterceptor FromAccessToken(string accessToken)
         {
-            Preconditions.CheckNotNull(accessToken);
+            GrpcPreconditions.CheckNotNull(accessToken);
             return new AsyncAuthInterceptor(async (context, metadata) =>
             {
                 metadata.Add(CreateBearerTokenHeader(accessToken));
diff --git a/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs b/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
index 5c9ab04812..5ba06d6509 100644
--- a/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
+++ b/src/csharp/Grpc.Core/AsyncAuthInterceptor.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -61,8 +61,8 @@ namespace Grpc.Core
         /// </summary>
         public AuthInterceptorContext(string serviceUrl, string methodName)
         {
-            this.serviceUrl = Preconditions.CheckNotNull(serviceUrl);
-            this.methodName = Preconditions.CheckNotNull(methodName);
+            this.serviceUrl = GrpcPreconditions.CheckNotNull(serviceUrl);
+            this.methodName = GrpcPreconditions.CheckNotNull(methodName);
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/CallCredentials.cs b/src/csharp/Grpc.Core/CallCredentials.cs
index a71c8904fe..7cd41d0480 100644
--- a/src/csharp/Grpc.Core/CallCredentials.cs
+++ b/src/csharp/Grpc.Core/CallCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -87,7 +87,7 @@ namespace Grpc.Core
         /// <param name="interceptor">authentication interceptor</param>
         public MetadataCredentials(AsyncAuthInterceptor interceptor)
         {
-            this.interceptor = Preconditions.CheckNotNull(interceptor);
+            this.interceptor = GrpcPreconditions.CheckNotNull(interceptor);
         }
 
         internal override CallCredentialsSafeHandle ToNativeCredentials()
@@ -111,7 +111,7 @@ namespace Grpc.Core
         /// <param name="credentials">credentials to compose</param>
         public CompositeCallCredentials(params CallCredentials[] credentials)
         {
-            Preconditions.CheckArgument(credentials.Length >= 2, "Composite credentials object can only be created from 2 or more credentials.");
+            GrpcPreconditions.CheckArgument(credentials.Length >= 2, "Composite credentials object can only be created from 2 or more credentials.");
             this.credentials = new List<CallCredentials>(credentials);
         }
 
diff --git a/src/csharp/Grpc.Core/CallInvocationDetails.cs b/src/csharp/Grpc.Core/CallInvocationDetails.cs
index 8228b8f317..52bfbe6edb 100644
--- a/src/csharp/Grpc.Core/CallInvocationDetails.cs
+++ b/src/csharp/Grpc.Core/CallInvocationDetails.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -85,11 +85,11 @@ namespace Grpc.Core
         /// <param name="options">Call options.</param>
         public CallInvocationDetails(Channel channel, string method, string host, Marshaller<TRequest> requestMarshaller, Marshaller<TResponse> responseMarshaller, CallOptions options)
         {
-            this.channel = Preconditions.CheckNotNull(channel, "channel");
-            this.method = Preconditions.CheckNotNull(method, "method");
+            this.channel = GrpcPreconditions.CheckNotNull(channel, "channel");
+            this.method = GrpcPreconditions.CheckNotNull(method, "method");
             this.host = host;
-            this.requestMarshaller = Preconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
-            this.responseMarshaller = Preconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
+            this.requestMarshaller = GrpcPreconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
+            this.responseMarshaller = GrpcPreconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
             this.options = options;
         }
 
diff --git a/src/csharp/Grpc.Core/CallOptions.cs b/src/csharp/Grpc.Core/CallOptions.cs
index 1fda80cb90..7bd95d4ba8 100644
--- a/src/csharp/Grpc.Core/CallOptions.cs
+++ b/src/csharp/Grpc.Core/CallOptions.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -176,13 +176,13 @@ namespace Grpc.Core
             {
                 if (propagationToken.Options.IsPropagateDeadline)
                 {
-                    Preconditions.CheckArgument(!newOptions.deadline.HasValue,
+                    GrpcPreconditions.CheckArgument(!newOptions.deadline.HasValue,
                         "Cannot propagate deadline from parent call. The deadline has already been set explicitly.");
                     newOptions.deadline = propagationToken.ParentDeadline;
                 }
                 if (propagationToken.Options.IsPropagateCancellation)
                 {
-                    Preconditions.CheckArgument(!newOptions.cancellationToken.CanBeCanceled,
+                    GrpcPreconditions.CheckArgument(!newOptions.cancellationToken.CanBeCanceled,
                         "Cannot propagate cancellation token from parent call. The cancellation token has already been set to a non-default value.");
                     newOptions.cancellationToken = propagationToken.ParentCancellationToken;
                 }
diff --git a/src/csharp/Grpc.Core/Channel.cs b/src/csharp/Grpc.Core/Channel.cs
index d8d43c7998..d7a482d86f 100644
--- a/src/csharp/Grpc.Core/Channel.cs
+++ b/src/csharp/Grpc.Core/Channel.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -68,7 +68,7 @@ namespace Grpc.Core
         /// <param name="options">Channel options.</param>
         public Channel(string target, ChannelCredentials credentials, IEnumerable<ChannelOption> options = null)
         {
-            this.target = Preconditions.CheckNotNull(target, "target");
+            this.target = GrpcPreconditions.CheckNotNull(target, "target");
             this.options = CreateOptionsDictionary(options);
             EnsureUserAgentChannelOption(this.options);
             this.environment = GrpcEnvironment.AddRef();
@@ -117,7 +117,7 @@ namespace Grpc.Core
         /// </summary>
         public Task WaitForStateChangedAsync(ChannelState lastObservedState, DateTime? deadline = null)
         {
-            Preconditions.CheckArgument(lastObservedState != ChannelState.FatalFailure,
+            GrpcPreconditions.CheckArgument(lastObservedState != ChannelState.FatalFailure,
                 "FatalFailure is a terminal state. No further state changes can occur.");
             var tcs = new TaskCompletionSource<object>();
             var deadlineTimespec = deadline.HasValue ? Timespec.FromDateTime(deadline.Value) : Timespec.InfFuture;
@@ -184,7 +184,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -221,7 +221,7 @@ namespace Grpc.Core
 
             bool success = false;
             handle.DangerousAddRef(ref success);
-            Preconditions.CheckState(success);
+            GrpcPreconditions.CheckState(success);
         }
 
         internal void RemoveCallReference(object call)
diff --git a/src/csharp/Grpc.Core/ChannelCredentials.cs b/src/csharp/Grpc.Core/ChannelCredentials.cs
index 5d96958e7c..03cda28400 100644
--- a/src/csharp/Grpc.Core/ChannelCredentials.cs
+++ b/src/csharp/Grpc.Core/ChannelCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -183,9 +183,9 @@ namespace Grpc.Core
         /// <param name="callCredentials">channelCredentials to compose</param>
         public CompositeChannelCredentials(ChannelCredentials channelCredentials, CallCredentials callCredentials)
         {
-            this.channelCredentials = Preconditions.CheckNotNull(channelCredentials);
-            this.callCredentials = Preconditions.CheckNotNull(callCredentials);
-            Preconditions.CheckArgument(channelCredentials.IsComposable, "Supplied channel credentials do not allow composition.");
+            this.channelCredentials = GrpcPreconditions.CheckNotNull(channelCredentials);
+            this.callCredentials = GrpcPreconditions.CheckNotNull(callCredentials);
+            GrpcPreconditions.CheckArgument(channelCredentials.IsComposable, "Supplied channel credentials do not allow composition.");
         }
 
         internal override ChannelCredentialsSafeHandle ToNativeCredentials()
diff --git a/src/csharp/Grpc.Core/ChannelOptions.cs b/src/csharp/Grpc.Core/ChannelOptions.cs
index d70673cf78..65e15e21e9 100644
--- a/src/csharp/Grpc.Core/ChannelOptions.cs
+++ b/src/csharp/Grpc.Core/ChannelOptions.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -73,8 +73,8 @@ namespace Grpc.Core
         public ChannelOption(string name, string stringValue)
         {
             this.type = OptionType.String;
-            this.name = Preconditions.CheckNotNull(name, "name");
-            this.stringValue = Preconditions.CheckNotNull(stringValue, "stringValue");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
+            this.stringValue = GrpcPreconditions.CheckNotNull(stringValue, "stringValue");
         }
 
         /// <summary>
@@ -85,7 +85,7 @@ namespace Grpc.Core
         public ChannelOption(string name, int intValue)
         {
             this.type = OptionType.Integer;
-            this.name = Preconditions.CheckNotNull(name, "name");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
             this.intValue = intValue;
         }
 
@@ -118,7 +118,7 @@ namespace Grpc.Core
         {
             get
             {
-                Preconditions.CheckState(type == OptionType.Integer);
+                GrpcPreconditions.CheckState(type == OptionType.Integer);
                 return intValue;
             }
         }
@@ -130,7 +130,7 @@ namespace Grpc.Core
         {
             get
             {
-                Preconditions.CheckState(type == OptionType.String);
+                GrpcPreconditions.CheckState(type == OptionType.String);
                 return stringValue;
             }
         }
diff --git a/src/csharp/Grpc.Core/ContextPropagationToken.cs b/src/csharp/Grpc.Core/ContextPropagationToken.cs
index 1d899b97fd..c0f638f837 100644
--- a/src/csharp/Grpc.Core/ContextPropagationToken.cs
+++ b/src/csharp/Grpc.Core/ContextPropagationToken.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -68,7 +68,7 @@ namespace Grpc.Core
 
         internal ContextPropagationToken(CallSafeHandle parentCall, DateTime deadline, CancellationToken cancellationToken, ContextPropagationOptions options)
         {
-            this.parentCall = Preconditions.CheckNotNull(parentCall);
+            this.parentCall = GrpcPreconditions.CheckNotNull(parentCall);
             this.deadline = deadline;
             this.cancellationToken = cancellationToken;
             this.options = options ?? ContextPropagationOptions.Default;
diff --git a/src/csharp/Grpc.Core/Grpc.Core.csproj b/src/csharp/Grpc.Core/Grpc.Core.csproj
index 8d7d2cae0d..3189835ccd 100644
--- a/src/csharp/Grpc.Core/Grpc.Core.csproj
+++ b/src/csharp/Grpc.Core/Grpc.Core.csproj
@@ -39,8 +39,7 @@
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="System" />
-    <Reference Include="System.Interactive.Async, Version=1.2.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35, processorArchitecture=MSIL">
-      <SpecificVersion>False</SpecificVersion>
+    <Reference Include="System.Interactive.Async">
       <HintPath>..\packages\Ix-Async.1.2.5\lib\net45\System.Interactive.Async.dll</HintPath>
     </Reference>
   </ItemGroup>
@@ -91,7 +90,6 @@
     <Compile Include="Internal\AsyncCallBase.cs" />
     <Compile Include="Internal\AsyncCallServer.cs" />
     <Compile Include="Internal\AsyncCall.cs" />
-    <Compile Include="Utils\Preconditions.cs" />
     <Compile Include="Internal\ServerCredentialsSafeHandle.cs" />
     <Compile Include="ServerCredentials.cs" />
     <Compile Include="Metadata.cs" />
@@ -130,6 +128,7 @@
     <Compile Include="Profiling\IProfiler.cs" />
     <Compile Include="Profiling\Profilers.cs" />
     <Compile Include="Internal\DefaultSslRootsOverride.cs" />
+    <Compile Include="Utils\GrpcPreconditions.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Grpc.Core.nuspec" />
diff --git a/src/csharp/Grpc.Core/GrpcEnvironment.cs b/src/csharp/Grpc.Core/GrpcEnvironment.cs
index f3aa3d79de..86b37b8660 100644
--- a/src/csharp/Grpc.Core/GrpcEnvironment.cs
+++ b/src/csharp/Grpc.Core/GrpcEnvironment.cs
@@ -83,7 +83,7 @@ namespace Grpc.Core
         {
             lock (staticLock)
             {
-                Preconditions.CheckState(refCount > 0);
+                GrpcPreconditions.CheckState(refCount > 0);
                 refCount--;
                 if (refCount == 0)
                 {
@@ -118,7 +118,7 @@ namespace Grpc.Core
         /// </summary>
         public static void SetLogger(ILogger customLogger)
         {
-            Preconditions.CheckNotNull(customLogger, "customLogger");
+            GrpcPreconditions.CheckNotNull(customLogger, "customLogger");
             logger = customLogger;
         }
 
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCall.cs b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
index 7dc4490281..2caba260b3 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCall.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCall.cs
@@ -99,7 +99,7 @@ namespace Grpc.Core.Internal
 
                 lock (myLock)
                 {
-                    Preconditions.CheckState(!started);
+                    GrpcPreconditions.CheckState(!started);
                     started = true;
                     Initialize(cq);
 
@@ -141,7 +141,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -168,7 +168,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -192,7 +192,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -217,7 +217,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!started);
+                GrpcPreconditions.CheckState(!started);
                 started = true;
 
                 Initialize(environment.CompletionQueue);
@@ -257,7 +257,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 call.StartSendCloseFromClient(HandleHalfclosed);
@@ -297,7 +297,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(finishedStatus.HasValue, "Status can only be accessed once the call has finished.");
+                GrpcPreconditions.CheckState(finishedStatus.HasValue, "Status can only be accessed once the call has finished.");
                 return finishedStatus.Value.Status;
             }
         }
@@ -310,7 +310,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(finishedStatus.HasValue, "Trailers can only be accessed once the call has finished.");
+                GrpcPreconditions.CheckState(finishedStatus.HasValue, "Trailers can only be accessed once the call has finished.");
                 return finishedStatus.Value.Trailers;
             }
         }
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs b/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
index 81a9a40fcc..45d4c3e078 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallBase.cs
@@ -79,9 +79,9 @@ namespace Grpc.Core.Internal
 
         public AsyncCallBase(Func<TWrite, byte[]> serializer, Func<byte[], TRead> deserializer, GrpcEnvironment environment)
         {
-            this.serializer = Preconditions.CheckNotNull(serializer);
-            this.deserializer = Preconditions.CheckNotNull(deserializer);
-            this.environment = Preconditions.CheckNotNull(environment);
+            this.serializer = GrpcPreconditions.CheckNotNull(serializer);
+            this.deserializer = GrpcPreconditions.CheckNotNull(deserializer);
+            this.environment = GrpcPreconditions.CheckNotNull(environment);
         }
 
         /// <summary>
@@ -91,7 +91,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckState(started);
+                GrpcPreconditions.CheckState(started);
                 cancelRequested = true;
 
                 if (!disposed)
@@ -135,7 +135,7 @@ namespace Grpc.Core.Internal
 
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 call.StartSendMessage(HandleSendFinished, payload, writeFlags, !initialMetadataSent);
@@ -154,7 +154,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckReadingAllowed();
 
                 call.StartReceiveMessage(HandleReadFinished);
@@ -204,22 +204,22 @@ namespace Grpc.Core.Internal
 
         protected void CheckSendingAllowed()
         {
-            Preconditions.CheckState(started);
+            GrpcPreconditions.CheckState(started);
             CheckNotCancelled();
-            Preconditions.CheckState(!disposed);
+            GrpcPreconditions.CheckState(!disposed);
 
-            Preconditions.CheckState(!halfcloseRequested, "Already halfclosed.");
-            Preconditions.CheckState(!finished, "Already finished.");
-            Preconditions.CheckState(sendCompletionDelegate == null, "Only one write can be pending at a time");
+            GrpcPreconditions.CheckState(!halfcloseRequested, "Already halfclosed.");
+            GrpcPreconditions.CheckState(!finished, "Already finished.");
+            GrpcPreconditions.CheckState(sendCompletionDelegate == null, "Only one write can be pending at a time");
         }
 
         protected virtual void CheckReadingAllowed()
         {
-            Preconditions.CheckState(started);
-            Preconditions.CheckState(!disposed);
+            GrpcPreconditions.CheckState(started);
+            GrpcPreconditions.CheckState(!disposed);
 
-            Preconditions.CheckState(!readingDone, "Stream has already been closed.");
-            Preconditions.CheckState(readCompletionDelegate == null, "Only one read can be pending at a time");
+            GrpcPreconditions.CheckState(!readingDone, "Stream has already been closed.");
+            GrpcPreconditions.CheckState(readCompletionDelegate == null, "Only one read can be pending at a time");
         }
 
         protected void CheckNotCancelled()
diff --git a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
index 6752d3fab3..b72cbd795f 100644
--- a/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
+++ b/src/csharp/Grpc.Core/Internal/AsyncCallServer.cs
@@ -53,7 +53,7 @@ namespace Grpc.Core.Internal
 
         public AsyncCallServer(Func<TResponse, byte[]> serializer, Func<byte[], TRequest> deserializer, GrpcEnvironment environment, Server server) : base(serializer, deserializer, environment)
         {
-            this.server = Preconditions.CheckNotNull(server);
+            this.server = GrpcPreconditions.CheckNotNull(server);
         }
 
         public void Initialize(CallSafeHandle call)
@@ -71,7 +71,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(call);
+                GrpcPreconditions.CheckNotNull(call);
 
                 started = true;
 
@@ -108,14 +108,14 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(headers, "metadata");
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(headers, "metadata");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
 
-                Preconditions.CheckState(!initialMetadataSent, "Response headers can only be sent once per call.");
-                Preconditions.CheckState(streamingWritesCounter == 0, "Response headers can only be sent before the first write starts.");
+                GrpcPreconditions.CheckState(!initialMetadataSent, "Response headers can only be sent once per call.");
+                GrpcPreconditions.CheckState(streamingWritesCounter == 0, "Response headers can only be sent before the first write starts.");
                 CheckSendingAllowed();
 
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
 
                 using (var metadataArray = MetadataArraySafeHandle.Create(headers))
                 {
@@ -136,7 +136,7 @@ namespace Grpc.Core.Internal
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
+                GrpcPreconditions.CheckNotNull(completionDelegate, "Completion delegate cannot be null");
                 CheckSendingAllowed();
 
                 using (var metadataArray = MetadataArraySafeHandle.Create(trailers))
@@ -177,7 +177,7 @@ namespace Grpc.Core.Internal
         protected override void CheckReadingAllowed()
         {
             base.CheckReadingAllowed();
-            Preconditions.CheckArgument(!cancelRequested);
+            GrpcPreconditions.CheckArgument(!cancelRequested);
         }
 
         protected override void OnAfterReleaseResources()
diff --git a/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs b/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
index 9d7a990c42..5c75b52e23 100644
--- a/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/CompletionQueueSafeHandle.cs
@@ -101,7 +101,7 @@ namespace Grpc.Core.Internal
         {
             bool success = false;
             shutdownRefcount.IncrementIfNonzero(ref success);
-            Preconditions.CheckState(success, "Shutdown has already been called");
+            GrpcPreconditions.CheckState(success, "Shutdown has already been called");
         }
 
         private void EndOp()
diff --git a/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs b/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
index 2796c959a3..3a293e1626 100644
--- a/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
+++ b/src/csharp/Grpc.Core/Internal/CompletionRegistry.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -59,7 +59,7 @@ namespace Grpc.Core.Internal
         public void Register(IntPtr key, OpCompletionDelegate callback)
         {
             environment.DebugStats.PendingBatchCompletions.Increment();
-            Preconditions.CheckState(dict.TryAdd(key, callback));
+            GrpcPreconditions.CheckState(dict.TryAdd(key, callback));
         }
 
         public void RegisterBatchCompletion(BatchContextSafeHandle ctx, BatchCompletionDelegate callback)
@@ -71,7 +71,7 @@ namespace Grpc.Core.Internal
         public OpCompletionDelegate Extract(IntPtr key)
         {
             OpCompletionDelegate value;
-            Preconditions.CheckState(dict.TryRemove(key, out value));
+            GrpcPreconditions.CheckState(dict.TryRemove(key, out value));
             environment.DebugStats.PendingBatchCompletions.Decrement();
             return value;
         }
diff --git a/src/csharp/Grpc.Core/Internal/Enums.cs b/src/csharp/Grpc.Core/Internal/Enums.cs
index b0eab2001b..098e7c0e99 100644
--- a/src/csharp/Grpc.Core/Internal/Enums.cs
+++ b/src/csharp/Grpc.Core/Internal/Enums.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -72,7 +72,7 @@ namespace Grpc.Core.Internal
         /// </summary>
         public static void CheckOk(this GRPCCallError callError)
         {
-            Preconditions.CheckState(callError == GRPCCallError.OK, "Call error: " + callError);
+            GrpcPreconditions.CheckState(callError == GRPCCallError.OK, "Call error: " + callError);
         }
     }
 
diff --git a/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs b/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
index 36b865c09c..e810ffcdd0 100644
--- a/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
+++ b/src/csharp/Grpc.Core/Internal/NativeMetadataCredentialsPlugin.cs
@@ -53,7 +53,7 @@ namespace Grpc.Core.Internal
 
         public NativeMetadataCredentialsPlugin(AsyncAuthInterceptor interceptor)
         {
-            this.interceptor = Preconditions.CheckNotNull(interceptor, "interceptor");
+            this.interceptor = GrpcPreconditions.CheckNotNull(interceptor, "interceptor");
             this.nativeInterceptor = NativeMetadataInterceptorHandler;
 
             // Make sure the callback doesn't get garbage collected until it is destroyed.
diff --git a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
index de66759b94..ccf144de2d 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCallHandler.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -78,10 +78,10 @@ namespace Grpc.Core.Internal
             var context = HandlerUtils.NewContext(newRpc, asyncCall.Peer, responseStream, asyncCall.CancellationToken);
             try
             {
-                Preconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
-                Preconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
                 var result = await handler(request, context).ConfigureAwait(false);
                 status = context.Status;
                 await responseStream.WriteAsync(result).ConfigureAwait(false);
@@ -134,10 +134,10 @@ namespace Grpc.Core.Internal
             var context = HandlerUtils.NewContext(newRpc, asyncCall.Peer, responseStream, asyncCall.CancellationToken);
             try
             {
-                Preconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(await requestStream.MoveNext().ConfigureAwait(false));
                 var request = requestStream.Current;
                 // TODO(jtattermusch): we need to read the full stream so that native callhandle gets deallocated.
-                Preconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
+                GrpcPreconditions.CheckArgument(!await requestStream.MoveNext().ConfigureAwait(false));
                 await handler(request, responseStream, context).ConfigureAwait(false);
                 status = context.Status;
             }
diff --git a/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs b/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
index a1d080c7f1..a50f357990 100644
--- a/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
+++ b/src/csharp/Grpc.Core/Internal/ServerCredentialsSafeHandle.cs
@@ -49,7 +49,7 @@ namespace Grpc.Core.Internal
 
         public static ServerCredentialsSafeHandle CreateSslCredentials(string pemRootCerts, string[] keyCertPairCertChainArray, string[] keyCertPairPrivateKeyArray, bool forceClientAuth)
         {
-            Preconditions.CheckArgument(keyCertPairCertChainArray.Length == keyCertPairPrivateKeyArray.Length);
+            GrpcPreconditions.CheckArgument(keyCertPairCertChainArray.Length == keyCertPairPrivateKeyArray.Length);
             return Native.grpcsharp_ssl_server_credentials_create(pemRootCerts,
                                                                   keyCertPairCertChainArray, keyCertPairPrivateKeyArray,
                                                                   new UIntPtr((ulong)keyCertPairCertChainArray.Length),
diff --git a/src/csharp/Grpc.Core/Internal/Timespec.cs b/src/csharp/Grpc.Core/Internal/Timespec.cs
index 148d877da5..754be4e035 100644
--- a/src/csharp/Grpc.Core/Internal/Timespec.cs
+++ b/src/csharp/Grpc.Core/Internal/Timespec.cs
@@ -141,8 +141,8 @@ namespace Grpc.Core.Internal
         /// </summary>
         public DateTime ToDateTime()
         {
-            Preconditions.CheckState(tv_nsec >= 0 && tv_nsec < NanosPerSecond);
-            Preconditions.CheckState(clock_type == GPRClockType.Realtime);
+            GrpcPreconditions.CheckState(tv_nsec >= 0 && tv_nsec < NanosPerSecond);
+            GrpcPreconditions.CheckState(clock_type == GPRClockType.Realtime);
 
             // fast path for InfFuture
             if (this.Equals(InfFuture))
@@ -195,7 +195,7 @@ namespace Grpc.Core.Internal
                 return Timespec.InfPast;
             }
 
-            Preconditions.CheckArgument(dateTime.Kind == DateTimeKind.Utc, "dateTime needs of kind DateTimeKind.Utc or be equal to DateTime.MaxValue or DateTime.MinValue.");
+            GrpcPreconditions.CheckArgument(dateTime.Kind == DateTimeKind.Utc, "dateTime needs of kind DateTimeKind.Utc or be equal to DateTime.MaxValue or DateTime.MinValue.");
 
             try
             {
diff --git a/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs b/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
index 95a8797e3e..e763c15025 100644
--- a/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
+++ b/src/csharp/Grpc.Core/Internal/UnmanagedLibrary.cs
@@ -65,7 +65,7 @@ namespace Grpc.Core.Internal
 
         public UnmanagedLibrary(string libraryPath)
         {
-            this.libraryPath = Preconditions.CheckNotNull(libraryPath);
+            this.libraryPath = GrpcPreconditions.CheckNotNull(libraryPath);
 
             if (!File.Exists(this.libraryPath))
             {
diff --git a/src/csharp/Grpc.Core/KeyCertificatePair.cs b/src/csharp/Grpc.Core/KeyCertificatePair.cs
index 6f691975e9..0fb6817986 100644
--- a/src/csharp/Grpc.Core/KeyCertificatePair.cs
+++ b/src/csharp/Grpc.Core/KeyCertificatePair.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -54,8 +54,8 @@ namespace Grpc.Core
         /// <param name="privateKey">PEM encoded private key.</param>
         public KeyCertificatePair(string certificateChain, string privateKey)
         {
-            this.certificateChain = Preconditions.CheckNotNull(certificateChain, "certificateChain");
-            this.privateKey = Preconditions.CheckNotNull(privateKey, "privateKey");
+            this.certificateChain = GrpcPreconditions.CheckNotNull(certificateChain, "certificateChain");
+            this.privateKey = GrpcPreconditions.CheckNotNull(privateKey, "privateKey");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Marshaller.cs b/src/csharp/Grpc.Core/Marshaller.cs
index 3493d2d38f..5847248c1a 100644
--- a/src/csharp/Grpc.Core/Marshaller.cs
+++ b/src/csharp/Grpc.Core/Marshaller.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -51,8 +51,8 @@ namespace Grpc.Core
         /// <param name="deserializer">Function that will be used to deserialize messages.</param>
         public Marshaller(Func<T, byte[]> serializer, Func<byte[], T> deserializer)
         {
-            this.serializer = Preconditions.CheckNotNull(serializer, "serializer");
-            this.deserializer = Preconditions.CheckNotNull(deserializer, "deserializer");
+            this.serializer = GrpcPreconditions.CheckNotNull(serializer, "serializer");
+            this.deserializer = GrpcPreconditions.CheckNotNull(deserializer, "deserializer");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Metadata.cs b/src/csharp/Grpc.Core/Metadata.cs
index 21bdf4f114..aa22f840d6 100644
--- a/src/csharp/Grpc.Core/Metadata.cs
+++ b/src/csharp/Grpc.Core/Metadata.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -179,7 +179,7 @@ namespace Grpc.Core
 
         private void CheckWriteable()
         {
-            Preconditions.CheckState(!readOnly, "Object is read only");
+            GrpcPreconditions.CheckState(!readOnly, "Object is read only");
         }
 
         #endregion
@@ -211,10 +211,10 @@ namespace Grpc.Core
             public Entry(string key, byte[] valueBytes)
             {
                 this.key = NormalizeKey(key);
-                Preconditions.CheckArgument(this.key.EndsWith(BinaryHeaderSuffix),
+                GrpcPreconditions.CheckArgument(this.key.EndsWith(BinaryHeaderSuffix),
                     "Key for binary valued metadata entry needs to have suffix indicating binary value.");
                 this.value = null;
-                Preconditions.CheckNotNull(valueBytes, "valueBytes");
+                GrpcPreconditions.CheckNotNull(valueBytes, "valueBytes");
                 this.valueBytes = new byte[valueBytes.Length];
                 Buffer.BlockCopy(valueBytes, 0, this.valueBytes, 0, valueBytes.Length);  // defensive copy to guarantee immutability
             }
@@ -227,9 +227,9 @@ namespace Grpc.Core
             public Entry(string key, string value)
             {
                 this.key = NormalizeKey(key);
-                Preconditions.CheckArgument(!this.key.EndsWith(BinaryHeaderSuffix),
+                GrpcPreconditions.CheckArgument(!this.key.EndsWith(BinaryHeaderSuffix),
                     "Key for ASCII valued metadata entry cannot have suffix indicating binary value.");
-                this.value = Preconditions.CheckNotNull(value, "value");
+                this.value = GrpcPreconditions.CheckNotNull(value, "value");
                 this.valueBytes = null;
             }
 
@@ -270,7 +270,7 @@ namespace Grpc.Core
             {
                 get
                 {
-                    Preconditions.CheckState(!IsBinary, "Cannot access string value of a binary metadata entry");
+                    GrpcPreconditions.CheckState(!IsBinary, "Cannot access string value of a binary metadata entry");
                     return value ?? Encoding.GetString(valueBytes);
                 }
             }
@@ -323,8 +323,8 @@ namespace Grpc.Core
 
             private static string NormalizeKey(string key)
             {
-                var normalized = Preconditions.CheckNotNull(key, "key").ToLower(CultureInfo.InvariantCulture);
-                Preconditions.CheckArgument(ValidKeyRegex.IsMatch(normalized), 
+                var normalized = GrpcPreconditions.CheckNotNull(key, "key").ToLower(CultureInfo.InvariantCulture);
+                GrpcPreconditions.CheckArgument(ValidKeyRegex.IsMatch(normalized), 
                     "Metadata entry key not valid. Keys can only contain lowercase alphanumeric characters, underscores and hyphens.");
                 return normalized;
             }
diff --git a/src/csharp/Grpc.Core/Method.cs b/src/csharp/Grpc.Core/Method.cs
index 99162a7d5d..3870076f7f 100644
--- a/src/csharp/Grpc.Core/Method.cs
+++ b/src/csharp/Grpc.Core/Method.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -106,10 +106,10 @@ namespace Grpc.Core
         public Method(MethodType type, string serviceName, string name, Marshaller<TRequest> requestMarshaller, Marshaller<TResponse> responseMarshaller)
         {
             this.type = type;
-            this.serviceName = Preconditions.CheckNotNull(serviceName, "serviceName");
-            this.name = Preconditions.CheckNotNull(name, "name");
-            this.requestMarshaller = Preconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
-            this.responseMarshaller = Preconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
+            this.serviceName = GrpcPreconditions.CheckNotNull(serviceName, "serviceName");
+            this.name = GrpcPreconditions.CheckNotNull(name, "name");
+            this.requestMarshaller = GrpcPreconditions.CheckNotNull(requestMarshaller, "requestMarshaller");
+            this.responseMarshaller = GrpcPreconditions.CheckNotNull(responseMarshaller, "responseMarshaller");
             this.fullName = GetFullName(serviceName, name);
         }
 
diff --git a/src/csharp/Grpc.Core/Server.cs b/src/csharp/Grpc.Core/Server.cs
index d120f95fdf..5d0fc6b1f0 100644
--- a/src/csharp/Grpc.Core/Server.cs
+++ b/src/csharp/Grpc.Core/Server.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -125,7 +125,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckState(!startRequested);
                 startRequested = true;
                 
                 handle.Start();
@@ -142,8 +142,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(startRequested);
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(startRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -162,8 +162,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(startRequested);
-                Preconditions.CheckState(!shutdownRequested);
+                GrpcPreconditions.CheckState(startRequested);
+                GrpcPreconditions.CheckState(!shutdownRequested);
                 shutdownRequested = true;
             }
 
@@ -181,7 +181,7 @@ namespace Grpc.Core
 
             bool success = false;
             handle.DangerousAddRef(ref success);
-            Preconditions.CheckState(success);
+            GrpcPreconditions.CheckState(success);
         }
 
         internal void RemoveCallReference(object call)
@@ -197,7 +197,7 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckState(!startRequested);
                 foreach (var entry in serviceDefinition.CallHandlers)
                 {
                     callHandlers.Add(entry.Key, entry.Value);
@@ -213,8 +213,8 @@ namespace Grpc.Core
         {
             lock (myLock)
             {
-                Preconditions.CheckNotNull(serverPort.Credentials, "serverPort");
-                Preconditions.CheckState(!startRequested);
+                GrpcPreconditions.CheckNotNull(serverPort.Credentials, "serverPort");
+                GrpcPreconditions.CheckState(!startRequested);
                 var address = string.Format("{0}:{1}", serverPort.Host, serverPort.Port);
                 int boundPort;
                 using (var nativeCredentials = serverPort.Credentials.ToNativeCredentials())
diff --git a/src/csharp/Grpc.Core/ServerCredentials.cs b/src/csharp/Grpc.Core/ServerCredentials.cs
index 3c6703d30e..456d331c9c 100644
--- a/src/csharp/Grpc.Core/ServerCredentials.cs
+++ b/src/csharp/Grpc.Core/ServerCredentials.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -90,11 +90,11 @@ namespace Grpc.Core
         public SslServerCredentials(IEnumerable<KeyCertificatePair> keyCertificatePairs, string rootCertificates, bool forceClientAuth)
         {
             this.keyCertificatePairs = new List<KeyCertificatePair>(keyCertificatePairs).AsReadOnly();
-            Preconditions.CheckArgument(this.keyCertificatePairs.Count > 0,
+            GrpcPreconditions.CheckArgument(this.keyCertificatePairs.Count > 0,
                 "At least one KeyCertificatePair needs to be provided.");
             if (forceClientAuth)
             {
-                Preconditions.CheckNotNull(rootCertificates,
+                GrpcPreconditions.CheckNotNull(rootCertificates,
                     "Cannot force client authentication unless you provide rootCertificates.");
             }
             this.rootCertificates = rootCertificates;
diff --git a/src/csharp/Grpc.Core/ServerPort.cs b/src/csharp/Grpc.Core/ServerPort.cs
index 598404d045..10ddcb782f 100644
--- a/src/csharp/Grpc.Core/ServerPort.cs
+++ b/src/csharp/Grpc.Core/ServerPort.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -62,9 +62,9 @@ namespace Grpc.Core
         /// <param name="credentials">credentials to use to secure this port.</param>
         public ServerPort(string host, int port, ServerCredentials credentials)
         {
-            this.host = Preconditions.CheckNotNull(host, "host");
+            this.host = GrpcPreconditions.CheckNotNull(host, "host");
             this.port = port;
-            this.credentials = Preconditions.CheckNotNull(credentials, "credentials");
+            this.credentials = GrpcPreconditions.CheckNotNull(credentials, "credentials");
         }
 
         /// <summary>
diff --git a/src/csharp/Grpc.Core/Utils/Preconditions.cs b/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
index a8ab603391..76bf04ce8b 100644
--- a/src/csharp/Grpc.Core/Utils/Preconditions.cs
+++ b/src/csharp/Grpc.Core/Utils/GrpcPreconditions.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -38,7 +38,7 @@ namespace Grpc.Core.Utils
     /// <summary>
     /// Utility methods to simplify checking preconditions in the code.
     /// </summary>
-    public static class Preconditions
+    public static class GrpcPreconditions
     {
         /// <summary>
         /// Throws <see cref="ArgumentException"/> if condition is false.
diff --git a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
index 26c6445c35..e2ad1a834b 100644
--- a/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
+++ b/src/csharp/Grpc.HealthCheck/HealthServiceImpl.cs
@@ -1,5 +1,5 @@
 #region Copyright notice and license
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -127,8 +127,8 @@ namespace Grpc.HealthCheck
         {
             public Key(string host, string service)
             {
-                this.Host = Preconditions.CheckNotNull(host);
-                this.Service = Preconditions.CheckNotNull(service);
+                this.Host = GrpcPreconditions.CheckNotNull(host);
+                this.Service = GrpcPreconditions.CheckNotNull(service);
             }
 
             readonly string Host;
diff --git a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
index e9e659cb1f..c4016012cb 100644
--- a/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ClientRunners.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -58,7 +58,7 @@ namespace Grpc.IntegrationTesting
         public static IClientRunner CreateStarted(ClientConfig config)
         {
             string target = config.ServerTargets.Single();
-            Grpc.Core.Utils.Preconditions.CheckArgument(config.LoadParams.LoadCase == LoadParams.LoadOneofCase.ClosedLoop);
+            GrpcPreconditions.CheckArgument(config.LoadParams.LoadCase == LoadParams.LoadOneofCase.ClosedLoop);
 
             var credentials = config.SecurityParams != null ? TestCredentials.CreateSslCredentials() : ChannelCredentials.Insecure;
             var channel = new Channel(target, credentials);
@@ -95,7 +95,7 @@ namespace Grpc.IntegrationTesting
         
         public SyncUnaryClientRunner(Channel channel, int payloadSize, HistogramParams histogramParams)
         {
-            this.channel = Grpc.Core.Utils.Preconditions.CheckNotNull(channel);
+            this.channel = GrpcPreconditions.CheckNotNull(channel);
             this.payloadSize = payloadSize;
             this.histogram = new Histogram(histogramParams.Resolution, histogramParams.MaxPossible);
 
diff --git a/src/csharp/Grpc.IntegrationTesting/Histogram.cs b/src/csharp/Grpc.IntegrationTesting/Histogram.cs
index 7e7cb2c4de..08a674d817 100644
--- a/src/csharp/Grpc.IntegrationTesting/Histogram.cs
+++ b/src/csharp/Grpc.IntegrationTesting/Histogram.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -66,8 +66,8 @@ namespace Grpc.IntegrationTesting
 
         public Histogram(double resolution, double maxPossible)
         {
-            Grpc.Core.Utils.Preconditions.CheckArgument(resolution > 0);
-            Grpc.Core.Utils.Preconditions.CheckArgument(maxPossible > 0);
+            GrpcPreconditions.CheckArgument(resolution > 0);
+            GrpcPreconditions.CheckArgument(maxPossible > 0);
             this.maxPossible = maxPossible;
             this.multiplier = 1.0 + resolution;
             this.oneOnLogMultiplier = 1.0 / Math.Log(1.0 + resolution);
diff --git a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
index e8be7758ce..9b09b9bdd3 100644
--- a/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
+++ b/src/csharp/Grpc.IntegrationTesting/ServerRunners.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -57,7 +57,7 @@ namespace Grpc.IntegrationTesting
         /// </summary>
         public static IServerRunner CreateStarted(ServerConfig config)
         {
-            Grpc.Core.Utils.Preconditions.CheckArgument(config.ServerType == ServerType.ASYNC_SERVER);
+            GrpcPreconditions.CheckArgument(config.ServerType == ServerType.ASYNC_SERVER);
             var credentials = config.SecurityParams != null ? TestCredentials.CreateSslServerCredentials() : ServerCredentials.Insecure;
 
             // TODO: qps_driver needs to setup payload properly...
@@ -83,7 +83,7 @@ namespace Grpc.IntegrationTesting
 
         public ServerRunnerImpl(Server server)
         {
-            this.server = Grpc.Core.Utils.Preconditions.CheckNotNull(server);
+            this.server = GrpcPreconditions.CheckNotNull(server);
         }
 
         public int BoundPort
diff --git a/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs b/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
index bb2918bf46..59ecebf5a2 100644
--- a/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
+++ b/src/csharp/Grpc.IntegrationTesting/WorkerServiceImpl.cs
@@ -1,6 +1,6 @@
 #region Copyright notice and license
 
-// Copyright 2015, Google Inc.
+// Copyright 2015-2016, Google Inc.
 // All rights reserved.
 //
 // Redistribution and use in source and binary forms, with or without
@@ -49,7 +49,7 @@ namespace Grpc.Testing
     {
         public async Task RunServer(IAsyncStreamReader<ServerArgs> requestStream, IServerStreamWriter<ServerStatus> responseStream, ServerCallContext context)
         {
-            Grpc.Core.Utils.Preconditions.CheckState(await requestStream.MoveNext());
+            GrpcPreconditions.CheckState(await requestStream.MoveNext());
             var serverConfig = requestStream.Current.Setup;
             var runner = ServerRunners.CreateStarted(serverConfig);
 
@@ -73,7 +73,7 @@ namespace Grpc.Testing
 
         public async Task RunClient(IAsyncStreamReader<ClientArgs> requestStream, IServerStreamWriter<ClientStatus> responseStream, ServerCallContext context)
         {
-            Grpc.Core.Utils.Preconditions.CheckState(await requestStream.MoveNext());
+            GrpcPreconditions.CheckState(await requestStream.MoveNext());
             var clientConfig = requestStream.Current.Setup;
             var runner = ClientRunners.CreateStarted(clientConfig);
 
diff --git a/src/node/index.js b/src/node/index.js
index 7eacdc67b1..1c197729d7 100644
--- a/src/node/index.js
+++ b/src/node/index.js
@@ -56,17 +56,18 @@ var grpc = require('./src/grpc_extension');
 /**
  * Load a gRPC object from an existing ProtoBuf.Reflect object.
  * @param {ProtoBuf.Reflect.Namespace} value The ProtoBuf object to load.
+ * @param {Object=} options Options to apply to the loaded object
  * @return {Object<string, *>} The resulting gRPC object
  */
-exports.loadObject = function loadObject(value) {
+exports.loadObject = function loadObject(value, options) {
   var result = {};
   if (value.className === 'Namespace') {
     _.each(value.children, function(child) {
-      result[child.name] = loadObject(child);
+      result[child.name] = loadObject(child, options);
     });
     return result;
   } else if (value.className === 'Service') {
-    return client.makeProtobufClientConstructor(value);
+    return client.makeProtobufClientConstructor(value, options);
   } else if (value.className === 'Message' || value.className === 'Enum') {
     return value.build();
   } else {
@@ -77,28 +78,45 @@ exports.loadObject = function loadObject(value) {
 var loadObject = exports.loadObject;
 
 /**
- * Load a gRPC object from a .proto file.
- * @param {string} filename The file to load
+ * Load a gRPC object from a .proto file. The options object can provide the
+ * following options:
+ * - convertFieldsToCamelCase: Loads this file with that option on protobuf.js
+ *   set as specified. See
+ *   https://github.com/dcodeIO/protobuf.js/wiki/Advanced-options for details
+ * - binaryAsBase64: deserialize bytes values as base64 strings instead of
+ *   Buffers. Defaults to false
+ * - longsAsStrings: deserialize long values as strings instead of objects.
+ *   Defaults to true
+ * @param {string|{root: string, file: string}} filename The file to load
  * @param {string=} format The file format to expect. Must be either 'proto' or
  *     'json'. Defaults to 'proto'
+ * @param {Object=} options Options to apply to the loaded file
  * @return {Object<string, *>} The resulting gRPC object
  */
-exports.load = function load(filename, format) {
+exports.load = function load(filename, format, options) {
   if (!format) {
     format = 'proto';
   }
+  var convertFieldsToCamelCaseOriginal = ProtoBuf.convertFieldsToCamelCase;
+  if(options && options.hasOwnProperty('convertFieldsToCamelCase')) {
+    ProtoBuf.convertFieldsToCamelCase = options.convertFieldsToCamelCase;
+  }
   var builder;
-  switch(format) {
-    case 'proto':
-    builder = ProtoBuf.loadProtoFile(filename);
-    break;
-    case 'json':
-    builder = ProtoBuf.loadJsonFile(filename);
-    break;
-    default:
-    throw new Error('Unrecognized format "' + format + '"');
+  try {
+    switch(format) {
+      case 'proto':
+      builder = ProtoBuf.loadProtoFile(filename);
+      break;
+      case 'json':
+      builder = ProtoBuf.loadJsonFile(filename);
+      break;
+      default:
+      throw new Error('Unrecognized format "' + format + '"');
+    }
+  } finally {
+    ProtoBuf.convertFieldsToCamelCase = convertFieldsToCamelCaseOriginal;
   }
-  return loadObject(builder.ns);
+  return loadObject(builder.ns, options);
 };
 
 /**
diff --git a/src/node/src/client.js b/src/node/src/client.js
index b5247a69ee..c02c44730e 100644
--- a/src/node/src/client.js
+++ b/src/node/src/client.js
@@ -698,13 +698,16 @@ exports.waitForClientReady = function(client, deadline, callback) {
  * Creates a constructor for clients for the given service
  * @param {ProtoBuf.Reflect.Service} service The service to generate a client
  *     for
+ * @param {Object=} options Options to apply to the client
  * @return {function(string, Object)} New client constructor
  */
-exports.makeProtobufClientConstructor =  function(service) {
-  var method_attrs = common.getProtobufServiceAttrs(service, service.name);
+exports.makeProtobufClientConstructor =  function(service, options) {
+  var method_attrs = common.getProtobufServiceAttrs(service, service.name,
+                                                    options);
   var Client = exports.makeClientConstructor(
       method_attrs, common.fullyQualifiedName(service));
   Client.service = service;
+  Client.service.grpc_options = options;
   return Client;
 };
 
diff --git a/src/node/src/common.js b/src/node/src/common.js
index 2e6c01c4d7..e5217608ec 100644
--- a/src/node/src/common.js
+++ b/src/node/src/common.js
@@ -44,9 +44,20 @@ var _ = require('lodash');
 /**
  * Get a function that deserializes a specific type of protobuf.
  * @param {function()} cls The constructor of the message type to deserialize
+ * @param {bool=} binaryAsBase64 Deserialize bytes fields as base64 strings
+ *     instead of Buffers. Defaults to false
+ * @param {bool=} longsAsStrings Deserialize long values as strings instead of
+ *     objects. Defaults to true
  * @return {function(Buffer):cls} The deserialization function
  */
-exports.deserializeCls = function deserializeCls(cls) {
+exports.deserializeCls = function deserializeCls(cls, binaryAsBase64,
+                                                 longsAsStrings) {
+  if (binaryAsBase64 === undefined || binaryAsBase64 === null) {
+    binaryAsBase64 = false;
+  }
+  if (longsAsStrings === undefined || longsAsStrings === null) {
+    longsAsStrings = true;
+  }
   /**
    * Deserialize a buffer to a message object
    * @param {Buffer} arg_buf The buffer to deserialize
@@ -55,7 +66,7 @@ exports.deserializeCls = function deserializeCls(cls) {
   return function deserialize(arg_buf) {
     // Convert to a native object with binary fields as Buffers (first argument)
     // and longs as strings (second argument)
-    return cls.decode(arg_buf).toRaw(false, true);
+    return cls.decode(arg_buf).toRaw(binaryAsBase64, longsAsStrings);
   };
 };
 
@@ -119,19 +130,28 @@ exports.wrapIgnoreNull = function wrapIgnoreNull(func) {
 /**
  * Return a map from method names to method attributes for the service.
  * @param {ProtoBuf.Reflect.Service} service The service to get attributes for
+ * @param {Object=} options Options to apply to these attributes
  * @return {Object} The attributes map
  */
-exports.getProtobufServiceAttrs = function getProtobufServiceAttrs(service) {
+exports.getProtobufServiceAttrs = function getProtobufServiceAttrs(service,
+                                                                   options) {
   var prefix = '/' + fullyQualifiedName(service) + '/';
+  var binaryAsBase64, longsAsStrings;
+  if (options) {
+    binaryAsBase64 = options.binaryAsBase64;
+    longsAsStrings = options.longsAsStrings;
+  }
   return _.object(_.map(service.children, function(method) {
     return [_.camelCase(method.name), {
       path: prefix + method.name,
       requestStream: method.requestStream,
       responseStream: method.responseStream,
       requestSerialize: serializeCls(method.resolvedRequestType.build()),
-      requestDeserialize: deserializeCls(method.resolvedRequestType.build()),
+      requestDeserialize: deserializeCls(method.resolvedRequestType.build(),
+                                     binaryAsBase64, longsAsStrings),
       responseSerialize: serializeCls(method.resolvedResponseType.build()),
-      responseDeserialize: deserializeCls(method.resolvedResponseType.build())
+      responseDeserialize: deserializeCls(method.resolvedResponseType.build(),
+                                     binaryAsBase64, longsAsStrings)
     }];
   }));
 };
diff --git a/src/node/src/server.js b/src/node/src/server.js
index e5aadcd565..0cf7ba3424 100644
--- a/src/node/src/server.js
+++ b/src/node/src/server.js
@@ -737,7 +737,12 @@ Server.prototype.addService = function(service, implementation) {
  *     method implementation for the provided service.
  */
 Server.prototype.addProtoService = function(service, implementation) {
-  this.addService(common.getProtobufServiceAttrs(service), implementation);
+  var options;
+  if (service.grpc_options) {
+    options = service.grpc_options;
+  }
+  this.addService(common.getProtobufServiceAttrs(service, options),
+                  implementation);
 };
 
 /**
diff --git a/src/node/test/common_test.js b/src/node/test/common_test.js
index 08ba429ed7..66a4205f82 100644
--- a/src/node/test/common_test.js
+++ b/src/node/test/common_test.js
@@ -1,6 +1,6 @@
 /*
  *
- * Copyright 2015, Google Inc.
+ * Copyright 2015-2016, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -42,7 +42,7 @@ var ProtoBuf = require('protobufjs');
 var messages_proto = ProtoBuf.loadProtoFile(
     __dirname + '/test_messages.proto').build();
 
-describe('Proto message serialize and deserialize', function() {
+describe('Proto message long int serialize and deserialize', function() {
   var longSerialize = common.serializeCls(messages_proto.LongValues);
   var longDeserialize = common.deserializeCls(messages_proto.LongValues);
   var pos_value = '314159265358979';
@@ -87,4 +87,52 @@ describe('Proto message serialize and deserialize', function() {
     assert.strictEqual(longDeserialize(serialized).sfixed_64.toString(),
                        neg_value);
   });
+  it('should deserialize as a number with the right option set', function() {
+    var longNumDeserialize = common.deserializeCls(messages_proto.LongValues,
+                                                   false, false);
+    var serialized = longSerialize({int_64: pos_value});
+    assert.strictEqual(typeof longDeserialize(serialized).int_64, 'string');
+    /* With the longsAsStrings option disabled, long values are represented as
+     * objects with 3 keys: low, high, and unsigned */
+    assert.strictEqual(typeof longNumDeserialize(serialized).int_64, 'object');
+  });
+});
+describe('Proto message bytes serialize and deserialize', function() {
+  var sequenceSerialize = common.serializeCls(messages_proto.SequenceValues);
+  var sequenceDeserialize = common.deserializeCls(
+      messages_proto.SequenceValues);
+  var sequenceBase64Deserialize = common.deserializeCls(
+      messages_proto.SequenceValues, true);
+  var buffer_val = new Buffer([0x69, 0xb7]);
+  var base64_val = 'abc=';
+  it('should preserve a buffer', function() {
+    var serialized = sequenceSerialize({bytes_field: buffer_val});
+    var deserialized = sequenceDeserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field.compare(buffer_val), 0);
+  });
+  it('should accept base64 encoded strings', function() {
+    var serialized = sequenceSerialize({bytes_field: base64_val});
+    var deserialized = sequenceDeserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field.compare(buffer_val), 0);
+  });
+  it('should output base64 encoded strings with an option set', function() {
+    var serialized = sequenceSerialize({bytes_field: base64_val});
+    var deserialized = sequenceBase64Deserialize(serialized);
+    assert.strictEqual(deserialized.bytes_field, base64_val);
+  });
+  /* The next two tests are specific tests to verify that issue
+   * https://github.com/grpc/grpc/issues/5174 has been fixed. They are skipped
+   * because they will not pass until a protobuf.js release has been published
+   * with a fix for https://github.com/dcodeIO/protobuf.js/issues/390 */
+  it.skip('should serialize a repeated field as packed by default', function() {
+    var expected_serialize = new Buffer([0x12, 0x01, 0x01, 0x0a]);
+    var serialized = sequenceSerialize({repeated_field: [10]});
+    assert.strictEqual(expected_serialize.compare(serialized), 0);
+  });
+  it.skip('should deserialize packed or unpacked repeated', function() {
+    var serialized = new Buffer([0x12, 0x01, 0x01, 0x0a]);
+    assert.doesNotThrow(function() {
+      sequenceDeserialize(serialized);
+    });
+  });
 });
diff --git a/src/node/test/test_messages.proto b/src/node/test/test_messages.proto
index c77a937d3f..9b8cb875ee 100644
--- a/src/node/test/test_messages.proto
+++ b/src/node/test/test_messages.proto
@@ -36,3 +36,8 @@ message LongValues {
   fixed64 fixed_64 = 4;
   sfixed64 sfixed_64 = 5;
 }
+
+message SequenceValues {
+  bytes bytes_field = 1;
+  repeated int32 repeated_field = 2;
+}
diff --git a/summerofcode/ideas.md b/summerofcode/ideas.md
new file mode 100644
index 0000000000..073262339b
--- /dev/null
+++ b/summerofcode/ideas.md
@@ -0,0 +1,4 @@
+Google Summer of Code 2016 gRPC Ideas
+=====================================
+
+(Skeleton for now.)
diff --git a/test/cpp/end2end/end2end_test.cc b/test/cpp/end2end/end2end_test.cc
index c8523847ab..ce8e4d2a10 100644
--- a/test/cpp/end2end/end2end_test.cc
+++ b/test/cpp/end2end/end2end_test.cc
@@ -51,11 +51,11 @@
 #include "src/core/security/credentials.h"
 #include "src/proto/grpc/testing/duplicate/echo_duplicate.grpc.pb.h"
 #include "src/proto/grpc/testing/echo.grpc.pb.h"
-#include "test/core/end2end/data/ssl_test_data.h"
 #include "test/core/util/port.h"
 #include "test/core/util/test_config.h"
 #include "test/cpp/end2end/test_service_impl.h"
 #include "test/cpp/util/string_ref_helper.h"
+#include "test/cpp/util/test_credentials_provider.h"
 
 using grpc::testing::EchoRequest;
 using grpc::testing::EchoResponse;
@@ -191,12 +191,14 @@ class TestServiceImplDupPkg
 
 class TestScenario {
  public:
-  TestScenario(bool proxy, bool tls) : use_proxy(proxy), use_tls(tls) {}
+  TestScenario(bool proxy, const grpc::string& creds_type)
+      : use_proxy(proxy), credentials_type(creds_type) {}
   void Log() const {
-    gpr_log(GPR_INFO, "Scenario: proxy %d, tls %d", use_proxy, use_tls);
+    gpr_log(GPR_INFO, "Scenario: proxy %d, credentials %s", use_proxy,
+            credentials_type.c_str());
   }
   bool use_proxy;
-  bool use_tls;
+  const grpc::string credentials_type;
 };
 
 class End2endTest : public ::testing::TestWithParam<TestScenario> {
@@ -220,14 +222,8 @@ class End2endTest : public ::testing::TestWithParam<TestScenario> {
     server_address_ << "127.0.0.1:" << port;
     // Setup server
     ServerBuilder builder;
-    auto server_creds = InsecureServerCredentials();
-    if (GetParam().use_tls) {
-      SslServerCredentialsOptions::PemKeyCertPair pkcp = {test_server1_key,
-                                                          test_server1_cert};
-      SslServerCredentialsOptions ssl_opts;
-      ssl_opts.pem_root_certs = "";
-      ssl_opts.pem_key_cert_pairs.push_back(pkcp);
-      server_creds = SslServerCredentials(ssl_opts);
+    auto server_creds = GetServerCredentials(GetParam().credentials_type);
+    if (GetParam().credentials_type != kInsecureCredentialsType) {
       server_creds->SetAuthMetadataProcessor(processor);
     }
     builder.AddListeningPort(server_address_.str(), server_creds);
@@ -246,12 +242,8 @@ class End2endTest : public ::testing::TestWithParam<TestScenario> {
     }
     EXPECT_TRUE(is_server_started_);
     ChannelArguments args;
-    auto channel_creds = InsecureChannelCredentials();
-    if (GetParam().use_tls) {
-      SslCredentialsOptions ssl_opts = {test_root_cert, "", ""};
-      args.SetSslTargetNameOverride("foo.test.google.fr");
-      channel_creds = SslCredentials(ssl_opts);
-    }
+    auto channel_creds =
+        GetChannelCredentials(GetParam().credentials_type, &args);
     if (!user_agent_prefix_.empty()) {
       args.SetUserAgentPrefix(user_agent_prefix_);
     }
@@ -941,7 +933,7 @@ TEST_P(End2endTest, ChannelState) {
 
 // Takes 10s.
 TEST_P(End2endTest, ChannelStateTimeout) {
-  if (GetParam().use_tls) {
+  if (GetParam().credentials_type != kInsecureCredentialsType) {
     return;
   }
   int port = grpc_pick_unused_port_or_die();
@@ -1150,7 +1142,7 @@ class SecureEnd2endTest : public End2endTest {
  protected:
   SecureEnd2endTest() {
     GPR_ASSERT(!GetParam().use_proxy);
-    GPR_ASSERT(GetParam().use_tls);
+    GPR_ASSERT(GetParam().credentials_type != kInsecureCredentialsType);
   }
 };
 
@@ -1373,21 +1365,42 @@ TEST_P(SecureEnd2endTest, ClientAuthContext) {
   EXPECT_EQ("*.test.youtube.com", ToString(auth_ctx->GetPeerIdentity()[2]));
 }
 
+std::vector<TestScenario> CreateTestScenarios(bool use_proxy,
+                                              bool test_insecure,
+                                              bool test_secure) {
+  std::vector<TestScenario> scenarios;
+  std::vector<grpc::string> credentials_types;
+  if (test_secure) {
+    credentials_types = GetSecureCredentialsTypeList();
+  }
+  if (test_insecure) {
+    credentials_types.push_back(kInsecureCredentialsType);
+  }
+  for (auto it = credentials_types.begin(); it != credentials_types.end();
+       ++it) {
+    scenarios.push_back(TestScenario(false, *it));
+    if (use_proxy) {
+      scenarios.push_back(TestScenario(true, *it));
+    }
+  }
+  return scenarios;
+}
+
 INSTANTIATE_TEST_CASE_P(End2end, End2endTest,
-                        ::testing::Values(TestScenario(false, false),
-                                          TestScenario(false, true)));
+                        ::testing::ValuesIn(CreateTestScenarios(false, true,
+                                                                true)));
 
 INSTANTIATE_TEST_CASE_P(End2endServerTryCancel, End2endServerTryCancelTest,
-                        ::testing::Values(TestScenario(false, false)));
+                        ::testing::ValuesIn(CreateTestScenarios(false, true,
+                                                                false)));
 
 INSTANTIATE_TEST_CASE_P(ProxyEnd2end, ProxyEnd2endTest,
-                        ::testing::Values(TestScenario(false, false),
-                                          TestScenario(false, true),
-                                          TestScenario(true, false),
-                                          TestScenario(true, true)));
+                        ::testing::ValuesIn(CreateTestScenarios(true, true,
+                                                                true)));
 
 INSTANTIATE_TEST_CASE_P(SecureEnd2end, SecureEnd2endTest,
-                        ::testing::Values(TestScenario(false, true)));
+                        ::testing::ValuesIn(CreateTestScenarios(false, false,
+                                                                true)));
 
 }  // namespace
 }  // namespace testing
diff --git a/test/cpp/util/test_credentials_provider.cc b/test/cpp/util/test_credentials_provider.cc
new file mode 100644
index 0000000000..1086e14258
--- /dev/null
+++ b/test/cpp/util/test_credentials_provider.cc
@@ -0,0 +1,82 @@
+
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include "test/cpp/util/test_credentials_provider.h"
+
+#include "test/core/end2end/data/ssl_test_data.h"
+
+namespace grpc {
+namespace testing {
+
+const char kTlsCredentialsType[] = "TLS_CREDENTIALS";
+
+std::shared_ptr<ChannelCredentials> GetChannelCredentials(
+    const grpc::string& type, ChannelArguments* args) {
+  if (type == kInsecureCredentialsType) {
+    return InsecureChannelCredentials();
+  } else if (type == kTlsCredentialsType) {
+    SslCredentialsOptions ssl_opts = {test_root_cert, "", ""};
+    args->SetSslTargetNameOverride("foo.test.google.fr");
+    return SslCredentials(ssl_opts);
+  } else {
+    gpr_log(GPR_ERROR, "Unsupported credentials type %s.", type.c_str());
+  }
+  return nullptr;
+}
+
+std::shared_ptr<ServerCredentials> GetServerCredentials(
+    const grpc::string& type) {
+  if (type == kInsecureCredentialsType) {
+    return InsecureServerCredentials();
+  } else if (type == kTlsCredentialsType) {
+    SslServerCredentialsOptions::PemKeyCertPair pkcp = {test_server1_key,
+                                                        test_server1_cert};
+    SslServerCredentialsOptions ssl_opts;
+    ssl_opts.pem_root_certs = "";
+    ssl_opts.pem_key_cert_pairs.push_back(pkcp);
+    return SslServerCredentials(ssl_opts);
+  } else {
+    gpr_log(GPR_ERROR, "Unsupported credentials type %s.", type.c_str());
+  }
+  return nullptr;
+}
+
+std::vector<grpc::string> GetSecureCredentialsTypeList() {
+  std::vector<grpc::string> types;
+  types.push_back(kTlsCredentialsType);
+  return types;
+}
+
+}  // namespace testing
+}  // namespace grpc
diff --git a/test/cpp/util/test_credentials_provider.h b/test/cpp/util/test_credentials_provider.h
new file mode 100644
index 0000000000..f7253051a9
--- /dev/null
+++ b/test/cpp/util/test_credentials_provider.h
@@ -0,0 +1,63 @@
+/*
+ *
+ * Copyright 2016, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#ifndef GRPC_TEST_CPP_UTIL_TEST_CREDENTIALS_PROVIDER_H
+#define GRPC_TEST_CPP_UTIL_TEST_CREDENTIALS_PROVIDER_H
+
+#include <memory>
+
+#include <grpc++/security/credentials.h>
+#include <grpc++/security/server_credentials.h>
+#include <grpc++/support/channel_arguments.h>
+
+namespace grpc {
+namespace testing {
+
+const char kInsecureCredentialsType[] = "INSECURE_CREDENTIALS";
+
+// Provide channel credentials according to the given type. Alter the channel
+// arguments if needed.
+std::shared_ptr<ChannelCredentials> GetChannelCredentials(
+    const grpc::string& type, ChannelArguments* args);
+
+// Provide server credentials according to the given type.
+std::shared_ptr<ServerCredentials> GetServerCredentials(
+    const grpc::string& type);
+
+// Provide a list of secure credentials type.
+std::vector<grpc::string> GetSecureCredentialsTypeList();
+
+}  // namespace testing
+}  // namespace grpc
+
+#endif  // GRPC_TEST_CPP_UTIL_TEST_CREDENTIALS_PROVIDER_H
diff --git a/tools/run_tests/run_node.bat b/tools/run_tests/run_node.bat
index f5cf01f095..ad9ca14b8b 100644
--- a/tools/run_tests/run_node.bat
+++ b/tools/run_tests/run_node.bat
@@ -29,4 +29,4 @@
 
 set JUNIT_REPORT_PATH=src\node\reports.xml
 set JUNIT_REPORT_STACK=1
-.\node_modules\.bin\mocha.cmd --reporter mocha-jenkins-reporter src\node\test
\ No newline at end of file
+.\node_modules\.bin\mocha.cmd --reporter mocha-jenkins-reporter --timeout 8000 src\node\test
\ No newline at end of file
diff --git a/tools/run_tests/run_node.sh b/tools/run_tests/run_node.sh
index 40f61d77cc..178584ae8e 100755
--- a/tools/run_tests/run_node.sh
+++ b/tools/run_tests/run_node.sh
@@ -41,10 +41,13 @@ cd $(dirname $0)/../..
 
 root=`pwd`
 
+test_directory='src/node/test'
+timeout=8000
+
 if [ "$CONFIG" = "gcov" ]
 then
   ./node_modules/.bin/istanbul cover --dir reports/node_coverage \
-    -x **/interop/* ./node_modules/.bin/_mocha -- --timeout 8000 src/node/test
+    -x **/interop/* ./node_modules/.bin/_mocha -- --timeout $timeout $test_directory
   cd build
   gcov Release/obj.target/grpc/ext/*.o
   lcov --base-directory . --directory . -c -o coverage.info
@@ -55,5 +58,7 @@ then
   echo '<html><head><meta http-equiv="refresh" content="0;URL=lcov-report/index.html"></head></html>' > \
     ../reports/node_coverage/index.html
 else
-  JUNIT_REPORT_PATH=src/node/reports.xml JUNIT_REPORT_STACK=1 ./node_modules/.bin/mocha --reporter mocha-jenkins-reporter src/node/test
+  JUNIT_REPORT_PATH=src/node/reports.xml JUNIT_REPORT_STACK=1 \
+    ./node_modules/.bin/mocha --timeout $timeout \
+    --reporter mocha-jenkins-reporter $test_directory
 fi
diff --git a/tools/run_tests/run_tests.py b/tools/run_tests/run_tests.py
index de3716bc88..0b3efa29e3 100755
--- a/tools/run_tests/run_tests.py
+++ b/tools/run_tests/run_tests.py
@@ -334,13 +334,14 @@ class RubyLanguage(object):
 
   def test_specs(self, config, args):
     return [config.job_spec(['tools/run_tests/run_ruby.sh'], None,
+                            timeout_seconds=10*60,
                             environ=_FORCE_ENVIRON_FOR_WRAPPERS)]
 
   def pre_build_steps(self):
     return [['tools/run_tests/pre_build_ruby.sh']]
 
   def make_targets(self, test_regex):
-    return ['static_c']
+    return []
 
   def make_options(self):
     return []
@@ -1197,4 +1198,3 @@ else:
   if BuildAndRunError.POST_TEST in errors:
     exit_code |= 4
   sys.exit(exit_code)
-
diff --git a/tools/run_tests/sources_and_headers.json b/tools/run_tests/sources_and_headers.json
index 560379b645..160d06ad64 100644
--- a/tools/run_tests/sources_and_headers.json
+++ b/tools/run_tests/sources_and_headers.json
@@ -4188,7 +4188,8 @@
       "test/cpp/util/cli_call.h", 
       "test/cpp/util/create_test_channel.h", 
       "test/cpp/util/string_ref_helper.h", 
-      "test/cpp/util/subprocess.h"
+      "test/cpp/util/subprocess.h", 
+      "test/cpp/util/test_credentials_provider.h"
     ], 
     "language": "c++", 
     "name": "grpc++_test_util", 
@@ -4204,7 +4205,9 @@
       "test/cpp/util/string_ref_helper.cc", 
       "test/cpp/util/string_ref_helper.h", 
       "test/cpp/util/subprocess.cc", 
-      "test/cpp/util/subprocess.h"
+      "test/cpp/util/subprocess.h", 
+      "test/cpp/util/test_credentials_provider.cc", 
+      "test/cpp/util/test_credentials_provider.h"
     ]
   }, 
   {
diff --git a/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj b/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj
index 3d353716a9..33860af620 100644
--- a/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj
+++ b/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj
@@ -153,6 +153,7 @@
     <ClInclude Include="$(SolutionDir)\..\test\cpp\util\create_test_channel.h" />
     <ClInclude Include="$(SolutionDir)\..\test\cpp\util\string_ref_helper.h" />
     <ClInclude Include="$(SolutionDir)\..\test\cpp\util\subprocess.h" />
+    <ClInclude Include="$(SolutionDir)\..\test\cpp\util\test_credentials_provider.h" />
   </ItemGroup>
   <ItemGroup>
     <ClCompile Include="$(SolutionDir)\..\src\proto\grpc\testing\echo_messages.pb.cc">
@@ -191,6 +192,8 @@
     </ClCompile>
     <ClCompile Include="$(SolutionDir)\..\test\cpp\util\subprocess.cc">
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\test\cpp\util\test_credentials_provider.cc">
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="$(SolutionDir)\..\vsprojects\vcxproj\.\grpc++\grpc++.vcxproj">
diff --git a/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj.filters b/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj.filters
index 27ac6751b9..b35ba1fd91 100644
--- a/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj.filters
+++ b/vsprojects/vcxproj/grpc++_test_util/grpc++_test_util.vcxproj.filters
@@ -28,6 +28,9 @@
     <ClCompile Include="$(SolutionDir)\..\test\cpp\util\subprocess.cc">
       <Filter>test\cpp\util</Filter>
     </ClCompile>
+    <ClCompile Include="$(SolutionDir)\..\test\cpp\util\test_credentials_provider.cc">
+      <Filter>test\cpp\util</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="$(SolutionDir)\..\test\cpp\end2end\test_service_impl.h">
@@ -48,6 +51,9 @@
     <ClInclude Include="$(SolutionDir)\..\test\cpp\util\subprocess.h">
       <Filter>test\cpp\util</Filter>
     </ClInclude>
+    <ClInclude Include="$(SolutionDir)\..\test\cpp\util\test_credentials_provider.h">
+      <Filter>test\cpp\util</Filter>
+    </ClInclude>
   </ItemGroup>
 
   <ItemGroup>