diff --git a/ClientTester/EchoClientTester/EchoDummyService/EchoDummyClientService.cs b/ClientTester/EchoClientTester/EchoDummyService/EchoDummyClientService.cs
index 9bcbc03..ad0fc48 100644
--- a/ClientTester/EchoClientTester/EchoDummyService/EchoDummyClientService.cs
+++ b/ClientTester/EchoClientTester/EchoDummyService/EchoDummyClientService.cs
@@ -72,6 +72,15 @@ public class EchoDummyClientService
 
     private async Task SendLoopAsync(CancellationToken ct)
     {
+        try
+        {
+            await Task.Delay(500, ct);
+        }
+        catch (OperationCanceledException)
+        {
+            return;
+        }
+
         int tick = 0;
 
         while (!ct.IsCancellationRequested)
@@ -140,6 +149,7 @@ public class EchoDummyClientService
                 totalAvgRtt += c.AvgRttMs;
                 rttClientCount++;
             }
+
             if (c.peer != null)
             {
                 connected++;
diff --git a/ClientTester/EchoClientTester/Program.cs b/ClientTester/EchoClientTester/Program.cs
index 2aa011f..857d3ee 100644
--- a/ClientTester/EchoClientTester/Program.cs
+++ b/ClientTester/EchoClientTester/Program.cs
@@ -9,7 +9,7 @@ class EcoClientTester
     public static readonly string CONNECTION_KEY = "test";
     public static readonly int CLIENT_COUNT = 100;
 
-    private async void StartEchoDummyTest()
+    private async Task StartEchoDummyTest()
     {
         try
         {
@@ -44,7 +44,7 @@ class EcoClientTester
         }
     }
 
-    private async void StartDummyTest()
+    private async Task StartDummyTest()
     {
         try
         {
@@ -105,12 +105,12 @@ class EcoClientTester
         if (choice == 1)
         {
             // 에코 서버 실행
-            tester.StartEchoDummyTest();
+            await tester.StartEchoDummyTest();
         }
         else if (choice == 2)
         {
             // 더미 클라 실행
-            tester.StartDummyTest();
+            await tester.StartDummyTest();
         }
     }
 }