start : new version

backend.py

@@ -50,7 +50,9 @@ class Backend():
 	###### backend object attributes
 #        self.devices = OrderedDict()  ### will contain the list of nodes in the network
 #        self.sensors = OrderedDict()  ### will contain the list of sensors (only) in the network
-	self.timestamps = {}	      ### will contain the time of the last values' update for each sensor
+        self.node_added = False
+        self.node_removed = False	    
+        self.timestamps = {}	      ### will contain the time of the last values' update for each sensor
         self.queryStages = {	      ### the diffrent stages that a node object gets through before being ready 
                 "None"                  :  1, # Query process hasn't started for this node
                 "ProtocolInfo"          :  2, # Retrieve protocol information
@@ -297,7 +299,7 @@ class Backend():
 
 
         if started:
-            print "Already started      !"
+            print "Already started "
             return 
         started = True
         self.network.start()