Separate  downstream object.
diff --git a/language-agent/DiscoveryService.proto b/language-agent/DiscoveryService.proto
index 7b166fe..d7aebad 100644
--- a/language-agent/DiscoveryService.proto
+++ b/language-agent/DiscoveryService.proto
@@ -23,7 +23,7 @@
 option csharp_namespace = "SkyWalking.NetworkProtocol";
 
 import "Common.proto";
-import "../Downstream.proto";
+import "Downstream.proto";
 
 service InstanceDiscoveryService {
     rpc registerInstance (ApplicationInstance) returns (ApplicationInstanceMapping) {
diff --git a/Downstream.proto b/language-agent/Downstream.proto
similarity index 100%
rename from Downstream.proto
rename to language-agent/Downstream.proto
diff --git a/language-agent/JVMMetricsService.proto b/language-agent/JVMMetricsService.proto
index e42f84a..eec0e45 100644
--- a/language-agent/JVMMetricsService.proto
+++ b/language-agent/JVMMetricsService.proto
@@ -22,7 +22,7 @@
 option java_package = "org.apache.skywalking.apm.network.language.agent";
 option csharp_namespace = "SkyWalking.NetworkProtocol";
 
-import "../Downstream.proto";
+import "Downstream.proto";
 
 service JVMMetricsService {
     rpc collect (JVMMetrics) returns (Downstream) {
diff --git a/service-mesh-probe/service-mesh.proto b/service-mesh-probe/service-mesh.proto
index c6c8d78..ceec3ef 100644
--- a/service-mesh-probe/service-mesh.proto
+++ b/service-mesh-probe/service-mesh.proto
@@ -21,10 +21,8 @@
 option java_multiple_files = true;
 option java_package = "org.apache.skywalking.apm.network.servicemesh";
 
-import "../Downstream.proto";
-
 service ServiceMeshMetricService {
-    rpc collect(stream serviceMeshMetric) returns (Downstream) {
+    rpc collect(stream serviceMeshMetric) returns (MeshProbeDownstream) {
     }
 }
 
@@ -56,5 +54,5 @@
     proxy = 2;
 }
 
-message Downstream {
+message MeshProbeDownstream {
 }