diff --git a/paddle/framework/CMakeLists.txt b/paddle/framework/CMakeLists.txt
index f7e5753ac2c238627b94050059620f87966ab4ed..8c34a77c20787e59376556c9d8f8ccbfa34d074b 100644
--- a/paddle/framework/CMakeLists.txt
+++ b/paddle/framework/CMakeLists.txt
@@ -7,4 +7,8 @@ cc_test(scope_test SRCS scope_test.cc)
 cc_test(enforce_test SRCS enforce_test.cc)
 proto_library(attr_type SRCS attr_type.proto)
 proto_library(op_proto SRCS op_proto.proto)
+
 cc_test(op_proto_test SRCS op_proto_test.cc DEPS op_proto attr_type protobuf)
+
+proto_library(net_proto SRCS net_proto.proto)
+cc_library(net SRCS net.cc DEPS net_proto attr_type op_proto)
diff --git a/paddle/framework/net.h b/paddle/framework/net.h
index 88bdf0bb68bffaa758cc8db723ed0377838516e5..b3064e4f90b773b7c0bcaaec66d1d47103e87793 100644
--- a/paddle/framework/net.h
+++ b/paddle/framework/net.h
@@ -14,6 +14,8 @@
 
 #pragma once
 
+#include "paddle/framework/net_proto.pb.h"
+#include "paddle/framework/op_proto.pb.h"
 #include "paddle/framework/scope.h"
 
 namespace paddle {
@@ -27,31 +29,11 @@ typedef int OpIndex;
  * keep updating if the concepts related are implemented.
  */
 
-// Operator's runtime context.
-struct OpContext {
-  int dev_id;
-  DevType dev_type{kCPU};
-  enum DevType { kCPU, kGPU };
-};
-
-// Proto definitions, use `struct`s for simpility.
-struct VarDesc {
-  std::string type;
-  std::vector<int> dims;
-};
-struct OpDesc {
-  std::string type;
-  std::vector<VarDesc> inputs;
-  std::vector<VarDesc> outputs;
-};
-struct struct NetDesc {
-  std::vector<OpDesc> ops;
-};
 class Operator {
  public:
   Operator(const OpDesc &def) {}
-  Error InferShape() {}
-  Error Run() {}
+  bool InferShape() {}
+  bool Run() {}
 };
 
 /**
@@ -73,7 +55,7 @@ class Net {
   /**
    * @brief Infer shapes of all inputs and outputs of operators.
    */
-  virtual Error InferShape(Scope *scope) override;
+  virtual bool InferShape(Scope *scope) override;
   /**
    * @brief Run the network.
    *
@@ -82,8 +64,8 @@ class Net {
    * environment for ops. `begin` and `end` specify the scope of `ops_` to run,
    * If no positive indexes are provided, all operators in `ops_` will run.
    */
-  virtual Error Run(Scope *scope, OpContext *context, OpIndex begin = -1,
-                    OpIndex end = -1) const = 0;
+  virtual bool Run(Scope *scope, OpContext *context, OpIndex begin = -1,
+                   OpIndex end = -1) const = 0;
 
   /**
    * @brief Add an Operator according to `def`.
@@ -93,12 +75,12 @@ class Net {
   /**
    * @brief Add optimizer operators acctording to `attrs`.
    */
-  virtual Error AddOptimizerOps(const OptAttrs &attrs) = 0;
+  virtual bool AddOptimizerOps(const OptAttrs &attrs) = 0;
 
   /**
    * @brief Add backward operators.
    */
-  virtual Error AddBackwardOps() = 0;
+  virtual bool AddBackwardOps() = 0;
 
   /**
    * @brief Create a network.
@@ -126,7 +108,7 @@ class PlainNet : public Net {
    * Infer all the operators' input and output varialbes' shapes, will be called
    * before every mini-batch
    */
-  virtual Error InferShape(Scope *scope) override;
+  virtual bool InferShape(Scope *scope) override;
 
   /**
    * @brief Run the network.
@@ -135,8 +117,8 @@ class PlainNet : public Net {
    * scope will be used instead. If no OpContext is provicded, default context
    * will be used.
    */
-  virtual Error Run(Scope *scope = nullptr, OpContext *context = nullptr,
-                    OpIndex begin = -1, OpIndex end = -1) const override;
+  virtual bool Run(Scope *scope = nullptr, OpContext *context = nullptr,
+                   OpIndex begin = -1, OpIndex end = -1) const override;
 
   /**
    * @brief Add an operator to this network.
@@ -146,12 +128,12 @@ class PlainNet : public Net {
   /**
    * @brief Add all optimizer operators related into the network.
    */
-  virtual Error AddOptimizerOps(const OptAttrs &attrs) override;
+  virtual bool AddOptimizerOps(const OptAttrs &attrs) override;
 
   /**
    * @brief Add all backward operators related into the network.
    */
-  virtual Error AddBackwardOps() override;
+  virtual bool AddBackwardOps() override;
 
  protected:
   /**
@@ -159,7 +141,7 @@ class PlainNet : public Net {
    *
    * Create operators accordding to `def`, will be called by the constructor.
    */
-  Error BuildNet(const NetDesc &def);
+  bool BuildNet(const NetDesc &def);
 
   /**
    * @brief Add an operator into this network.
diff --git a/paddle/framework/net_proto.proto b/paddle/framework/net_proto.proto
new file mode 100644
index 0000000000000000000000000000000000000000..e9aed8f349b80925fc492707393b03835e73fcdd
--- /dev/null
+++ b/paddle/framework/net_proto.proto
@@ -0,0 +1,16 @@
+syntax="proto2";
+package paddle.framework;
+
+import "op_proto.proto"
+
+message NetDesc {
+  // network identification
+  optional string name = 1;
+  // operator contains in network
+  repeated OpProto operators = 2;
+  // network type to run with. e.g "plainNet", "DAG"
+  optional string type = 3;
+  // num worker always
+  optional int32 num_workers = 4;
+}
+