diff --git a/clients/client-linux.py b/clients/client-linux.py
index 8fa8bb2..c946300 100755
--- a/clients/client-linux.py
+++ b/clients/client-linux.py
@@ -14,7 +14,9 @@ USER = "s01"
 PORT = 35601
 PASSWORD = "USER_DEFAULT_PASSWORD"
 INTERVAL = 1
-PORBEPORT = 80
+PROBEPORT = 80
+PROBE_PROTOCOL_PREFER = "ipv4"  # ipv4, ipv6
+PING_PACKET_HISTORY_LEN = 100
 CU = "cu.tz.cloudcpp.com"
 CT = "ct.tz.cloudcpp.com"
 CM = "cm.tz.cloudcpp.com"
@@ -26,8 +28,13 @@ import re
 import os
 import sys
 import json
+import errno
 import subprocess
 import threading
+try:
+    from queue import Queue     # python3
+except ImportError:
+    from Queue import Queue     # python2
 
 def get_uptime():
     with open('/proc/uptime', 'r') as f:
@@ -116,7 +123,7 @@ def ip_status():
     ip_check = 0
     for i in [CU, CT, CM]:
         try:
-            socket.create_connection((i, PORBEPORT), timeout=1).close()
+            socket.create_connection((i, PROBEPORT), timeout=1).close()
         except:
             ip_check += 1
     if ip_check >= 2:
@@ -156,27 +163,38 @@ netSpeed = {
 
 def _ping_thread(host, mark, port):
     lostPacket = 0
-    allPacket = 0
-    startTime = time.time()
+    packet_queue = Queue(maxsize=PING_PACKET_HISTORY_LEN)
+
+    IP = host
+    if host.count(':') < 1:     # if not plain ipv6 address, means ipv4 address or hostname
+        try:
+            if PROBE_PROTOCOL_PREFER == 'ipv4':
+                IP = socket.getaddrinfo(host, None, socket.AF_INET)[0][4][0]
+            else:
+                IP = socket.getaddrinfo(host, None, socket.AF_INET6)[0][4][0]
+        except Exception:
+                pass
 
     while True:
+        if packet_queue.full():
+            if packet_queue.get() == 0:
+                lostPacket -= 1
         try:
             b = timeit.default_timer()
-            socket.create_connection((host, port), timeout=1).close()
-            pingTime[mark] = int((timeit.default_timer()-b)*1000)
-        except:
-            lostPacket += 1
-        finally:
-            allPacket += 1
+            socket.create_connection((IP, port), timeout=1).close()
+            pingTime[mark] = int((timeit.default_timer() - b) * 1000)
+            packet_queue.put(1)
+        except socket.error as error:
+            if error.errno == errno.ECONNREFUSED:
+                pingTime[mark] = int((timeit.default_timer() - b) * 1000)
+                packet_queue.put(1)
+            #elif error.errno == errno.ETIMEDOUT:
+            else:
+                lostPacket += 1
+                packet_queue.put(0)
 
-        if allPacket > 100:
-            lostRate[mark] = float(lostPacket) / allPacket
-
-        endTime = time.time()
-        if endTime - startTime > 3600:
-            lostPacket = 0
-            allPacket = 0
-            startTime = endTime
+        if packet_queue.qsize() > 30:
+            lostRate[mark] = float(lostPacket) / packet_queue.qsize()
 
         time.sleep(INTERVAL)
 
@@ -211,7 +229,7 @@ def get_realtime_date():
         kwargs={
             'host': CU,
             'mark': '10010',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t2 = threading.Thread(
@@ -219,7 +237,7 @@ def get_realtime_date():
         kwargs={
             'host': CT,
             'mark': '189',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t3 = threading.Thread(
@@ -227,7 +245,7 @@ def get_realtime_date():
         kwargs={
             'host': CM,
             'mark': '10086',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t4 = threading.Thread(
diff --git a/clients/client-psutil.py b/clients/client-psutil.py
index 799ce56..80a9810 100755
--- a/clients/client-psutil.py
+++ b/clients/client-psutil.py
@@ -15,7 +15,9 @@ USER = "s01"
 PORT = 35601
 PASSWORD = "USER_DEFAULT_PASSWORD"
 INTERVAL = 1
-PORBEPORT = 80
+PROBEPORT = 80
+PROBE_PROTOCOL_PREFER = "ipv4"  # ipv4, ipv6
+PING_PACKET_HISTORY_LEN = 100
 CU = "cu.tz.cloudcpp.com"
 CT = "ct.tz.cloudcpp.com"
 CM = "cm.tz.cloudcpp.com"
@@ -28,6 +30,11 @@ import json
 import psutil
 import sys
 import threading
+import threading
+try:
+    from queue import Queue     # python3
+except ImportError:
+    from Queue import Queue     # python2
 
 def get_uptime():
     return int(time.time() - psutil.boot_time())
@@ -100,7 +107,7 @@ def ip_status():
     ip_check = 0
     for i in [CU, CT, CM]:
         try:
-            socket.create_connection((i, PORBEPORT), timeout=1).close()
+            socket.create_connection((i, PROBEPORT), timeout=1).close()
         except:
             ip_check += 1
     if ip_check >= 2:
@@ -140,27 +147,38 @@ netSpeed = {
 
 def _ping_thread(host, mark, port):
     lostPacket = 0
-    allPacket = 0
-    startTime = time.time()
+    packet_queue = Queue(maxsize=PING_PACKET_HISTORY_LEN)
+
+    IP = host
+    if host.count(':') < 1:     # if not plain ipv6 address, means ipv4 address or hostname
+        try:
+            if PROBE_PROTOCOL_PREFER == 'ipv4':
+                IP = socket.getaddrinfo(host, None, socket.AF_INET)[0][4][0]
+            else:
+                IP = socket.getaddrinfo(host, None, socket.AF_INET6)[0][4][0]
+        except Exception:
+                pass
 
     while True:
+        if packet_queue.full():
+            if packet_queue.get() == 0:
+                lostPacket -= 1
         try:
             b = timeit.default_timer()
-            socket.create_connection((host, port), timeout=1).close()
+            socket.create_connection((IP, port), timeout=1).close()
             pingTime[mark] = int((timeit.default_timer() - b) * 1000)
-        except:
-            lostPacket += 1
-        finally:
-            allPacket += 1
+            packet_queue.put(1)
+        except socket.error as error:
+            if error.errno == errno.ECONNREFUSED:
+                pingTime[mark] = int((timeit.default_timer() - b) * 1000)
+                packet_queue.put(1)
+            #elif error.errno == errno.ETIMEDOUT:
+            else:
+                lostPacket += 1
+                packet_queue.put(0)
 
-        if allPacket > 100:
-            lostRate[mark] = float(lostPacket) / allPacket
-
-        endTime = time.time()
-        if endTime - startTime > 3600:
-            lostPacket = 0
-            allPacket = 0
-            startTime = endTime
+        if packet_queue.qsize() > 30:
+            lostRate[mark] = float(lostPacket) / packet_queue.qsize()
 
         time.sleep(INTERVAL)
 
@@ -191,7 +209,7 @@ def get_realtime_date():
         kwargs={
             'host': CU,
             'mark': '10010',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t2 = threading.Thread(
@@ -199,7 +217,7 @@ def get_realtime_date():
         kwargs={
             'host': CT,
             'mark': '189',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t3 = threading.Thread(
@@ -207,7 +225,7 @@ def get_realtime_date():
         kwargs={
             'host': CM,
             'mark': '10086',
-            'port': PORBEPORT
+            'port': PROBEPORT
         }
     )
     t4 = threading.Thread(