diff --git a/src/conf/xp/1_ping b/src/conf/xp/1_ping
index 9b7a9f7..79a7eb9 100644
--- a/src/conf/xp/1_ping
+++ b/src/conf/xp/1_ping
@@ -1,2 +1,3 @@
 xpType:ping
 pingCount:16
+rmem:87380 87380 87380
diff --git a/src/mpExperience.py b/src/mpExperience.py
index 772b230..7cafaac 100644
--- a/src/mpExperience.py
+++ b/src/mpExperience.py
@@ -15,6 +15,7 @@ class MpExperience:
 		self.clean()
 	
 	def prepare(self):
+		self.setupSysctl()
 		self.runTcpDump()
 		pass
 
@@ -26,8 +27,51 @@ class MpExperience:
 				"killall tcpdump")
 		self.mpTopo.commandTo(self.mpConfig.server,
 				"killall tcpdump")
+		self.backUpSysctl()
 		pass
 
+	def setupSysctl(self):
+		self.saveSysctl()
+		self.writeSysctl()
+
+	def saveSysctl(self):
+		self.sysctlBUP = {}
+		for k in MpParamXp.sysctlKey:
+			sysctlKey = MpParamXp.sysctlKey[k]
+			cmd = self.cmdReadSysctl(sysctlKey)
+			val = self.mpTopo.notNSCommand(cmd)
+			if val == "Error":
+				print("oooops can't get sysctl " + sysctlKey)
+			else:
+				self.sysctlBUP[k] = val.split(" ",2)[2][:-1]
+
+	def cmdReadSysctl(self, key):
+		s = "sysctl " + key
+		return s
+
+	def cmdWriteSysctl(self, key, value):
+		s = self.cmdReadSysctl(key)
+		s = s + "=\"" + str(value) + "\""
+		return s
+
+	def writeSysctl(self):
+		for k in self.sysctlBUP:
+			sysctlKey = MpParamXp.sysctlKey[k]
+			sysctlValue = self.xpParam.getParam(k)
+			cmd = self.cmdWriteSysctl(sysctlKey,sysctlValue)
+			val = self.mpTopo.notNSCommand(cmd)
+			if val == "Error":
+				print("oooops can't set sysctl " + sysctlKey)
+
+	def backUpSysctl(self):
+		for k in self.sysctlBUP:
+			sysctlKey = MpParamXp.sysctlKey[k]
+			sysctlValue = self.sysctlBUP[k]
+			cmd = self.cmdWriteSysctl(sysctlKey,sysctlValue)
+			val = self.mpTopo.notNSCommand(cmd)
+			if val == "Error":
+				print("oooops can't set sysctl " + sysctlKey)
+
 	def runTcpDump(self):
 		#todo : replace filename by cst
 		if self.xpParam.getParam(MpParamXp.CLIENTPCAP) == "yes" :
diff --git a/src/mpMininetBuilder.py b/src/mpMininetBuilder.py
index 0b5945b..4a5e30b 100644
--- a/src/mpMininetBuilder.py
+++ b/src/mpMininetBuilder.py
@@ -2,6 +2,7 @@ from mininet.topo import Topo
 from mininet.net import Mininet
 from mininet.link import TCLink
 from mininet.cli import CLI
+from subprocess import Popen, PIPE
 
 class MpMininetBuilder(Topo):
 	def __init__(self):
@@ -10,6 +11,13 @@ class MpMininetBuilder(Topo):
 	
 	def commandTo(self, who, cmd):
 		who.cmd(cmd)
+
+	def notNSCommand(self, cmd):
+		p = Popen(cmd, shell=True, stdout=PIPE, stderr=PIPE)
+		stdout, stderr = p.communicate()
+		if stderr:
+			return "Error"
+		return stdout
 	
 	def startNetwork(self):
 		self.net = Mininet(topo=self,link=TCLink)
diff --git a/src/mpParamXp.py b/src/mpParamXp.py
index 5d9addf..e0bb176 100644
--- a/src/mpParamXp.py
+++ b/src/mpParamXp.py
@@ -3,6 +3,7 @@ from mpParam import MpParam
 class MpParamXp(MpParam):
 
 	RMEM       = "rmem"
+	KERNELPM   = "kpm"
 	CLIENTPCAP = "clientPcap"
 	SERVERPCAP = "serverPcap"
 	XPTYPE     = "xpType"
@@ -16,9 +17,19 @@ class MpParamXp(MpParam):
 	NCSERVERPORT = "ncServerPort"
 	NCCLIENTPORT = "ncClientPort"
 
+	# global sysctl
+	sysctlKey = {}
+	sysctlKey[RMEM] = "net.ipv4.tcp_rmem"
+	sysctlKey[KERNELPM] = "net.mptcp.mptcp_path_manager"
+
+	sysctlListClient = []
+	sysctlListServer = []
+
 	defaultValue = {}
 
-	defaultValue[RMEM] = "x y z"
+	defaultValue[RMEM] = "10240 87380 16777216"
+	defaultValue[KERNELPM] = "fullmesh"
+
 	defaultValue[CLIENTPCAP] = "no"
 	defaultValue[SERVERPCAP] = "no"
 	defaultValue[XPTYPE] = "ping"
diff --git a/src/mpTopo.py b/src/mpTopo.py
index 4b65081..a6d4e4a 100644
--- a/src/mpTopo.py
+++ b/src/mpTopo.py
@@ -20,6 +20,13 @@ class MpTopo:
 		self.logFile.write(who.__str__() + " : " + cmd + "\n")
 		self.topoBuilder.commandTo(who, cmd)
 
+	def notNSCommand(self, cmd):
+		"""
+		mainly use for not namespace sysctl.
+		"""
+		self.logFile.write("Not_NS" + " : " + cmd + "\n")
+		return self.topoBuilder.notNSCommand(cmd)
+
 	def getHost(self, who):
 		return self.topoBuilder.getHost(who)