diff --git a/esds/node.py b/esds/node.py
index 12e7a13..4bfae71 100644
--- a/esds/node.py
+++ b/esds/node.py
@@ -3,11 +3,12 @@ from esds.rcode import RCode
 
 class Node:
     available_node_id=0
-    def __init__(self,src,interfaces):
+    def __init__(self,src,interfaces,grp):
         """
         self.chest: contains mutex protected data
         """
         self.node_id=Node.available_node_id
+        self.grp=grp # Node group
         Node.available_node_id+=1 # Refresh node id
         self.src=src # Store the node source code
         self.args=None # Store the node arguments (passed through Simulator.create_node()
diff --git a/esds/platform.py b/esds/platform.py
index 341ca13..40f8301 100644
--- a/esds/platform.py
+++ b/esds/platform.py
@@ -58,6 +58,7 @@ class YAMLPlatformFile:
             "node_count": 0,
             "implementations": [],
             "arguments": [],
+            "groups": dict(),
             "interfaces": dict()
         }
 
@@ -145,6 +146,14 @@ class YAMLPlatformFile:
             self.default["node_count"]=nodes["count"]
         else:
             self.parsing_error("node count not provided")
+        if "groups" in nodes:
+            if type(nodes["groups"]) != list:
+                self.parsing_error("nodes groups should be a list")
+            for grp in nodes["groups"]:
+                words=grp.split()
+                r=UnitsParser.node_range(words[0],self.default["node_count"])
+                for node in r:
+                    self.default["groups"][node]=words[1]
         if "implementations" in nodes:
             if type(nodes["implementations"]) != list:
                 self.parsing_error("nodes implementations should be a list of file path")
@@ -210,7 +219,10 @@ class YAMLPlatformFile:
         ##### Create simulator
         simulator=Simulator(self.default["interfaces"])
         for node_id in range(0,self.default["node_count"]):
-            simulator.create_node(self.default["implementations"][node_id], args=self.default["arguments"][node_id])
+            if node_id in self.default["groups"]:
+                simulator.create_node(self.default["implementations"][node_id], args=self.default["arguments"][node_id],grp=self.default["groups"][node_id])
+            else:
+                simulator.create_node(self.default["implementations"][node_id], args=self.default["arguments"][node_id])
         ##### Run simulation
         simulator.run(
             breakpoints=self.default["breakpoints"],
diff --git a/esds/simulator.py b/esds/simulator.py
index 90ad427..2253a49 100644
--- a/esds/simulator.py
+++ b/esds/simulator.py
@@ -75,18 +75,19 @@ class Simulator:
                         event[2][5]=new_duration
         self.netmat=netmat
           
-    def create_node(self, src, args=None):
+    def create_node(self, src, args=None, grp="def"):
         """
         Create a node thread and run it
         """
-        node=Node(src, self.netmat.keys())
+        node=Node(src, self.netmat.keys(), grp)
         self.nodes.append(node)
         thread=threading.Thread(target=node.run,args=[args]) # There must be "daemon=True" as a parameter, but we removed it to be compatible with older version of python
         thread.start()
 
     def log(self,msg,node=None):
-        src = "esds" if node is None else "n"+str(node)
-        logline="[t="+str(self.time_truncated)+",src="+src+"] "+msg
+        logline="[t="+str(self.time_truncated)+",src=esds] "+msg
+        if node is not None:
+            logline="[t="+str(self.time_truncated)+",src=n"+str(node.node_id)+",grp="+str(node.grp)+"] "+msg
         if self.debug is not None:
             self.debug.append_log(logline)
         print(logline)
@@ -118,7 +119,7 @@ class Simulator:
                 break
             elif not timeout_remove_only:
                 if node["request"] == "log":
-                    self.log(node.rargs,node=node.node_id)
+                    self.log(node.rargs,node=node)
                     node["state"]="running"
                     node.rqueue.put(("log",RCode.SUCCESS))
                 elif node["request"] == "timeout_add":
@@ -140,7 +141,7 @@ class Simulator:
                     node["state"]="running"
                     node.rqueue.put(("notify_remove",RCode.SUCCESS))
                 elif node["request"] == "abort":
-                    self.log("Simulation aborted: "+node.rargs,node=node.node_id)
+                    self.log("Simulation aborted: "+node.rargs,node=node)
                     exit(1)
                 elif node["request"] == "read":
                     node["state"]="running"
@@ -159,12 +160,12 @@ class Simulator:
                 elif node["request"] == "turn_on":
                     node["state"]="running"
                     node.rqueue.put(("turn_on",RCode.SUCCESS))
-                    self.log("Turned on",node=node.node_id)
+                    self.log("Turned on",node=node)
                 elif node["request"] == "turn_off":
                     # Update node state after turning off
                     node["state"]="running"
                     node.rqueue.put(("turn_off",RCode.SUCCESS))
-                    self.log("Turned off",node=node.node_id)
+                    self.log("Turned off",node=node)
                     # We cancel communication after node has turned off
                     self.cancel_communications(node.node_id,reason=RCode.RECEIVER_TURNED_OFF)
                 elif node["request"] == "send_cancel":
@@ -281,7 +282,7 @@ class Simulator:
         if len(selector) != 0:
             self.events=self.events[~np.array(selector)]
             for node in notify:
-                self.log("Interferences on "+interface,node=node)
+                self.log("Interferences on "+interface,node=self.nodes[node])
         return status
     
     def sync_node_blocking(self, node):
@@ -294,7 +295,7 @@ class Simulator:
                 interface, data, datasize, dst, receiver_required=node.rargs
                 if dst != None: 
                     if not (dst >=0 and dst <=len(self.nodes)):
-                        self.log("Invalid dst used in send() or sendt(), node "+str(dst)+" not found", node=node.node_id)
+                        self.log("Invalid dst used in send() or sendt(), node "+str(dst)+" not found", node=node)
                         exit(1)
                 if not self.communicate(interface, node.node_id, dst, data, datasize,receiver_required):
                     node["state"]="running"
@@ -323,7 +324,7 @@ class Simulator:
         """
         nsrc=self.nodes[src]
         if self.netmat[interface]["is_wired"]:
-            self.log("Send "+str(datasize)+" bytes to n"+str(dst)+" on "+interface,node=src)
+            self.log("Send "+str(datasize)+" bytes to n"+str(dst)+" on "+interface,node=nsrc)
             if not self.nodes[dst]["turned_on"] and receiver_required:
                 return(False)
             self.update_sharing(dst,1,interface) # Update sharing first
@@ -331,7 +332,7 @@ class Simulator:
             duration=datasize*8/(self.netmat[interface]["bandwidth"][src,dst]/self.sharing[interface][dst])+self.netmat[interface]["latency"][src,dst]
             self.add_event(0,duration+self.time,(src,dst,interface,data,datasize,duration,datasize,self.time,self.nodes[dst]["turned_on"],receiver_required))
         else:
-            self.log("Send "+str(datasize)+" bytes on "+interface,node=src)
+            self.log("Send "+str(datasize)+" bytes on "+interface,node=nsrc)
             for dst in self.list_receivers(nsrc,interface):
                 if self.nodes[dst]["turned_on"]:
                     duration=datasize*8/self.netmat[interface]["bandwidth"][src,dst]+self.netmat[interface]["latency"][src,dst]
@@ -418,7 +419,7 @@ class Simulator:
                         if perform_delivery:
                             dst["interfaces"][interface].put((data,start_at,self.time))
                             dst["interfaces_queue_size"][interface]+=1
-                            self.log("Receive "+str(datasize)+" bytes on "+interface,node=int(dst_id))
+                            self.log("Receive "+str(datasize)+" bytes on "+interface,node=dst)
                             # If node is receiving makes it consume (this way if there is a timeout, it will be removed!)
                             if dst["state"] == "call_blocking" and dst["request"] == "receive":
                                 dst["interfaces_queue_size"][interface]-=1
@@ -437,7 +438,7 @@ class Simulator:
                             if perform_delivery:
                                 dst["interfaces"][interface].put((data,start_at,self.time))
                                 dst["interfaces_queue_size"][interface]+=1
-                                self.log("Receive "+str(datasize)+" bytes on "+interface,node=int(dst_id))
+                                self.log("Receive "+str(datasize)+" bytes on "+interface,node=dst)
                                 # If node is receiving makes it consume (this way if there is a timeout, it will be removed!)
                                 if dst["state"] == "call_blocking" and dst["request"] == "receive":
                                     dst["interfaces_queue_size"][interface]-=1
diff --git a/example/platform.yaml b/example/platform.yaml
index a549350..ea3f760 100644
--- a/example/platform.yaml
+++ b/example/platform.yaml
@@ -28,6 +28,10 @@ nodes:
     # 0-@ receiver.py     is equivalent to     0-4 receiver.py
     implementations:
         - all sender.py
+    # Allow you to assign a group to each node (visible in ESDS log reports)
+    # If not specified, group is "def" for default
+    groups:
+        - 0-2 A
     # Node implementation arguments
     # arguments keys are ranges of nodes, and values are passed to the specified nodes
     arguments:
diff --git a/tests/api_log_5n/out b/tests/api_log_5n/out
index 7d89c56..a52cc3e 100644
--- a/tests/api_log_5n/out
+++ b/tests/api_log_5n/out
@@ -1,21 +1,21 @@
-[t=0.000,src=n0] A
-[t=0.000,src=n0] B
-[t=0.000,src=n0] C
-[t=0.000,src=n0] D
-[t=0.000,src=n1] A
-[t=0.000,src=n1] B
-[t=0.000,src=n1] C
-[t=0.000,src=n1] D
-[t=0.000,src=n2] A
-[t=0.000,src=n2] B
-[t=0.000,src=n2] C
-[t=0.000,src=n2] D
-[t=0.000,src=n3] A
-[t=0.000,src=n3] B
-[t=0.000,src=n3] C
-[t=0.000,src=n3] D
-[t=0.000,src=n4] A
-[t=0.000,src=n4] B
-[t=0.000,src=n4] C
-[t=0.000,src=n4] D
+[t=0.000,src=n0,grp=def] A
+[t=0.000,src=n0,grp=def] B
+[t=0.000,src=n0,grp=def] C
+[t=0.000,src=n0,grp=def] D
+[t=0.000,src=n1,grp=def] A
+[t=0.000,src=n1,grp=def] B
+[t=0.000,src=n1,grp=def] C
+[t=0.000,src=n1,grp=def] D
+[t=0.000,src=n2,grp=def] A
+[t=0.000,src=n2,grp=def] B
+[t=0.000,src=n2,grp=def] C
+[t=0.000,src=n2,grp=def] D
+[t=0.000,src=n3,grp=def] A
+[t=0.000,src=n3,grp=def] B
+[t=0.000,src=n3,grp=def] C
+[t=0.000,src=n3,grp=def] D
+[t=0.000,src=n4,grp=def] A
+[t=0.000,src=n4,grp=def] B
+[t=0.000,src=n4,grp=def] C
+[t=0.000,src=n4,grp=def] D
 [t=0.000,src=esds] Simulation ends
diff --git a/tests/api_read_clock_2n/out b/tests/api_read_clock_2n/out
index c3cb2b9..82f7446 100644
--- a/tests/api_read_clock_2n/out
+++ b/tests/api_read_clock_2n/out
@@ -1,7 +1,7 @@
-[t=0.000,src=n0] Clock is 0.0s
-[t=0.000,src=n1] Clock is 0.0s
-[t=5698.126,src=n0] Clock is 5698.1256s
-[t=5698.126,src=n0] Clock is 5698.1256s
-[t=5698.126,src=n1] Clock is 5698.1256s
-[t=5698.126,src=n1] Clock is 5698.1256s
+[t=0.000,src=n0,grp=def] Clock is 0.0s
+[t=0.000,src=n1,grp=def] Clock is 0.0s
+[t=5698.126,src=n0,grp=def] Clock is 5698.1256s
+[t=5698.126,src=n0,grp=def] Clock is 5698.1256s
+[t=5698.126,src=n1,grp=def] Clock is 5698.1256s
+[t=5698.126,src=n1,grp=def] Clock is 5698.1256s
 [t=5698.126,src=esds] Simulation ends
diff --git a/tests/api_read_eth0_ncom_2s1r/out b/tests/api_read_eth0_ncom_2s1r/out
index 087e62b..1bbcf61 100644
--- a/tests/api_read_eth0_ncom_2s1r/out
+++ b/tests/api_read_eth0_ncom_2s1r/out
@@ -1,9 +1,9 @@
-[t=0.000,src=n2] eth0 is 0
-[t=624.000,src=n2] eth0 is 0
-[t=1248.000,src=n0] Send 50 bytes to n2 on eth0
-[t=1249.000,src=n2] eth0 is 1
-[t=1249.000,src=n1] Send 50 bytes to n2 on eth0
-[t=1250.000,src=n2] eth0 is 2
-[t=1513.667,src=n2] Receive 50 bytes on eth0
-[t=1514.667,src=n2] Receive 50 bytes on eth0
+[t=0.000,src=n2,grp=def] eth0 is 0
+[t=624.000,src=n2,grp=def] eth0 is 0
+[t=1248.000,src=n0,grp=def] Send 50 bytes to n2 on eth0
+[t=1249.000,src=n2,grp=def] eth0 is 1
+[t=1249.000,src=n1,grp=def] Send 50 bytes to n2 on eth0
+[t=1250.000,src=n2,grp=def] eth0 is 2
+[t=1513.667,src=n2,grp=def] Receive 50 bytes on eth0
+[t=1514.667,src=n2,grp=def] Receive 50 bytes on eth0
 [t=1514.667,src=esds] Simulation ends
diff --git a/tests/api_read_order_ncom_1s2r/out b/tests/api_read_order_ncom_1s2r/out
index 9172791..972857b 100644
--- a/tests/api_read_order_ncom_1s2r/out
+++ b/tests/api_read_order_ncom_1s2r/out
@@ -1,6 +1,6 @@
-[t=0.000,src=n0] wlan0 is 0
-[t=0.000,src=n2] wlan0 is 0
-[t=0.000,src=n1] Send 1 bytes on wlan0
-[t=1.000,src=n0] Receive 1 bytes on wlan0
-[t=1.000,src=n2] Receive 1 bytes on wlan0
+[t=0.000,src=n0,grp=def] wlan0 is 0
+[t=0.000,src=n2,grp=def] wlan0 is 0
+[t=0.000,src=n1,grp=def] Send 1 bytes on wlan0
+[t=1.000,src=n0,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n2,grp=def] Receive 1 bytes on wlan0
 [t=1.000,src=esds] Simulation ends
diff --git a/tests/api_read_wlan0_ncom_2s1r/out b/tests/api_read_wlan0_ncom_2s1r/out
index 93543eb..e3fc10c 100644
--- a/tests/api_read_wlan0_ncom_2s1r/out
+++ b/tests/api_read_wlan0_ncom_2s1r/out
@@ -1,11 +1,11 @@
-[t=0.000,src=n2] wlan0 is 0
-[t=624.000,src=n2] wlan0 is 0
-[t=1248.000,src=n0] Send 50 bytes on wlan0
-[t=1249.000,src=n2] wlan0 is 1
-[t=1249.000,src=n1] Send 50 bytes on wlan0
-[t=1250.000,src=n2] wlan0 is 2
-[t=1381.333,src=n1] Receive 50 bytes on wlan0
-[t=1381.333,src=n2] Receive 50 bytes on wlan0
-[t=1382.333,src=n0] Receive 50 bytes on wlan0
-[t=1382.333,src=n2] Receive 50 bytes on wlan0
+[t=0.000,src=n2,grp=def] wlan0 is 0
+[t=624.000,src=n2,grp=def] wlan0 is 0
+[t=1248.000,src=n0,grp=def] Send 50 bytes on wlan0
+[t=1249.000,src=n2,grp=def] wlan0 is 1
+[t=1249.000,src=n1,grp=def] Send 50 bytes on wlan0
+[t=1250.000,src=n2,grp=def] wlan0 is 2
+[t=1381.333,src=n1,grp=def] Receive 50 bytes on wlan0
+[t=1381.333,src=n2,grp=def] Receive 50 bytes on wlan0
+[t=1382.333,src=n0,grp=def] Receive 50 bytes on wlan0
+[t=1382.333,src=n2,grp=def] Receive 50 bytes on wlan0
 [t=1382.333,src=esds] Simulation ends
diff --git a/tests/api_receivet0_eth0_1s1r/out b/tests/api_receivet0_eth0_1s1r/out
index 0116a1d..a9de55b 100644
--- a/tests/api_receivet0_eth0_1s1r/out
+++ b/tests/api_receivet0_eth0_1s1r/out
@@ -1,5 +1,5 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
-[t=0.000,src=n1] Receive failed code=RCode.TIMEOUT_EXPIRE
-[t=1.000,src=n1] Receive 1 bytes on eth0
-[t=1.000,src=n1] Received: Hello World!
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=0.000,src=n1,grp=def] Receive failed code=RCode.TIMEOUT_EXPIRE
+[t=1.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=1.000,src=n1,grp=def] Received: Hello World!
 [t=1.000,src=esds] Simulation ends
diff --git a/tests/api_receivet_eth0_1s1r/out b/tests/api_receivet_eth0_1s1r/out
index 3573164..d969b73 100644
--- a/tests/api_receivet_eth0_1s1r/out
+++ b/tests/api_receivet_eth0_1s1r/out
@@ -1,8 +1,8 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
-[t=1.000,src=n1] Receive 1 bytes on eth0
-[t=1.000,src=n1] Received: Hello World!
-[t=1.000,src=n0] Send 1 bytes to n1 on eth0
-[t=1.500,src=n1] Receive failed code=RCode.TIMEOUT_EXPIRE
-[t=2.000,src=n1] Receive 1 bytes on eth0
-[t=2.000,src=n1] Received: Hello World!
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=1.500,src=n1,grp=def] Receive failed code=RCode.TIMEOUT_EXPIRE
+[t=2.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=2.000,src=n1,grp=def] Received: Hello World!
 [t=2.000,src=esds] Simulation ends
diff --git a/tests/api_send0_eth0_1s1r/out b/tests/api_send0_eth0_1s1r/out
index 3ffee9f..c5a17fe 100644
--- a/tests/api_send0_eth0_1s1r/out
+++ b/tests/api_send0_eth0_1s1r/out
@@ -1,16 +1,16 @@
-[t=0.000,src=n0] Send 0 bytes to n1 on eth0
-[t=0.000,src=n1] Receive 0 bytes on eth0
-[t=0.000,src=n1] Received: Hello World!
-[t=0.000,src=n0] Send 0 bytes to n1 on eth0
-[t=0.000,src=n1] Receive 0 bytes on eth0
-[t=0.000,src=n1] Received: Hello World!
-[t=1.000,src=n0] Send 0 bytes to n1 on eth0
-[t=1.000,src=n1] Receive 0 bytes on eth0
-[t=1.000,src=n1] Received: Hello World!
-[t=3.000,src=n0] Send 0 bytes to n1 on eth0
-[t=3.000,src=n1] Receive 0 bytes on eth0
-[t=3.000,src=n1] Received: Hello World!
-[t=3.000,src=n0] Send 0 bytes to n1 on eth0
-[t=3.000,src=n1] Receive 0 bytes on eth0
-[t=3.000,src=n1] Received: Hello World!
+[t=0.000,src=n0,grp=def] Send 0 bytes to n1 on eth0
+[t=0.000,src=n1,grp=def] Receive 0 bytes on eth0
+[t=0.000,src=n1,grp=def] Received: Hello World!
+[t=0.000,src=n0,grp=def] Send 0 bytes to n1 on eth0
+[t=0.000,src=n1,grp=def] Receive 0 bytes on eth0
+[t=0.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n0,grp=def] Send 0 bytes to n1 on eth0
+[t=1.000,src=n1,grp=def] Receive 0 bytes on eth0
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=3.000,src=n0,grp=def] Send 0 bytes to n1 on eth0
+[t=3.000,src=n1,grp=def] Receive 0 bytes on eth0
+[t=3.000,src=n1,grp=def] Received: Hello World!
+[t=3.000,src=n0,grp=def] Send 0 bytes to n1 on eth0
+[t=3.000,src=n1,grp=def] Receive 0 bytes on eth0
+[t=3.000,src=n1,grp=def] Received: Hello World!
 [t=3.000,src=esds] Simulation ends
diff --git a/tests/api_send_4interfaces_1s2r/out b/tests/api_send_4interfaces_1s2r/out
index 1d40d0a..8a65a12 100644
--- a/tests/api_send_4interfaces_1s2r/out
+++ b/tests/api_send_4interfaces_1s2r/out
@@ -1,14 +1,14 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
-[t=1.000,src=n1] Receive 1 bytes on wlan0
-[t=1.000,src=n0] Send 1 bytes on wlan1
-[t=2.000,src=n1] Receive 1 bytes on wlan1
-[t=2.000,src=n2] Receive 1 bytes on wlan1
-[t=2.000,src=n0] Send 1 bytes to n1 on eth0
-[t=3.000,src=n1] Receive 1 bytes on eth0
-[t=3.000,src=n0] Send 1 bytes to n2 on eth0
-[t=4.000,src=n2] Receive 1 bytes on eth0
-[t=4.000,src=n0] Send 1 bytes to n1 on eth1
-[t=4.500,src=n1] Receive 1 bytes on eth1
-[t=4.500,src=n0] Send 1 bytes to n2 on eth1
-[t=5.000,src=n2] Receive 1 bytes on eth1
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n0,grp=def] Send 1 bytes on wlan1
+[t=2.000,src=n1,grp=def] Receive 1 bytes on wlan1
+[t=2.000,src=n2,grp=def] Receive 1 bytes on wlan1
+[t=2.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=3.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=3.000,src=n0,grp=def] Send 1 bytes to n2 on eth0
+[t=4.000,src=n2,grp=def] Receive 1 bytes on eth0
+[t=4.000,src=n0,grp=def] Send 1 bytes to n1 on eth1
+[t=4.500,src=n1,grp=def] Receive 1 bytes on eth1
+[t=4.500,src=n0,grp=def] Send 1 bytes to n2 on eth1
+[t=5.000,src=n2,grp=def] Receive 1 bytes on eth1
 [t=5.000,src=esds] Simulation ends
diff --git a/tests/api_send_eth0_1s1r/out b/tests/api_send_eth0_1s1r/out
index d01fb93..76d98c6 100644
--- a/tests/api_send_eth0_1s1r/out
+++ b/tests/api_send_eth0_1s1r/out
@@ -1,18 +1,18 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
-[t=1.000,src=n1] Receive 1 bytes on eth0
-[t=1.000,src=n1] Received: Hello World!
-[t=1.000,src=n0] Send 1 bytes to n1 on eth0
-[t=2.000,src=n1] Receive 1 bytes on eth0
-[t=3.000,src=n0] Send 15 bytes to n1 on eth0
-[t=3.000,src=n1] Received: Hello World!
-[t=3.000,src=n1] Turned off
-[t=4.000,src=n1] Turned on
-[t=5.000,src=n1] Receive failed code=RCode.TIMEOUT_EXPIRE
-[t=18.000,src=n0] End transmission
-[t=18.000,src=n0] Send 15 bytes to n1 on eth0
-[t=33.000,src=n1] Receive 15 bytes on eth0
-[t=33.000,src=n0] End transmission
-[t=33.000,src=n0] Send 15 bytes to n1 on eth0
-[t=35.000,src=n1] Turned off
-[t=35.000,src=n0] End transmission
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=2.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=3.000,src=n0,grp=def] Send 15 bytes to n1 on eth0
+[t=3.000,src=n1,grp=def] Received: Hello World!
+[t=3.000,src=n1,grp=def] Turned off
+[t=4.000,src=n1,grp=def] Turned on
+[t=5.000,src=n1,grp=def] Receive failed code=RCode.TIMEOUT_EXPIRE
+[t=18.000,src=n0,grp=def] End transmission
+[t=18.000,src=n0,grp=def] Send 15 bytes to n1 on eth0
+[t=33.000,src=n1,grp=def] Receive 15 bytes on eth0
+[t=33.000,src=n0,grp=def] End transmission
+[t=33.000,src=n0,grp=def] Send 15 bytes to n1 on eth0
+[t=35.000,src=n1,grp=def] Turned off
+[t=35.000,src=n0,grp=def] End transmission
 [t=35.000,src=esds] Simulation ends
diff --git a/tests/api_send_eth0_2s1r/out b/tests/api_send_eth0_2s1r/out
index 663e5cf..00a7508 100644
--- a/tests/api_send_eth0_2s1r/out
+++ b/tests/api_send_eth0_2s1r/out
@@ -1,7 +1,7 @@
-[t=0.000,src=n0] Send 1 bytes to n2 on eth0
-[t=0.000,src=n1] Send 1 bytes to n2 on eth0
-[t=2.000,src=n2] Receive 1 bytes on eth0
-[t=2.000,src=n2] Receive 1 bytes on eth0
-[t=2.000,src=n2] Received: Hello World from 0!
-[t=2.000,src=n2] Received: Hello World from 1!
+[t=0.000,src=n0,grp=def] Send 1 bytes to n2 on eth0
+[t=0.000,src=n1,grp=def] Send 1 bytes to n2 on eth0
+[t=2.000,src=n2,grp=def] Receive 1 bytes on eth0
+[t=2.000,src=n2,grp=def] Receive 1 bytes on eth0
+[t=2.000,src=n2,grp=def] Received: Hello World from 0!
+[t=2.000,src=n2,grp=def] Received: Hello World from 1!
 [t=2.000,src=esds] Simulation ends
diff --git a/tests/api_send_eth0_3s1r/out b/tests/api_send_eth0_3s1r/out
index 714a4c8..7122a5b 100644
--- a/tests/api_send_eth0_3s1r/out
+++ b/tests/api_send_eth0_3s1r/out
@@ -1,40 +1,40 @@
-[t=0.000,src=n0] Send 1 bytes to n3 on eth0
-[t=0.000,src=n1] Send 1 bytes to n3 on eth0
-[t=0.000,src=n2] Send 1 bytes to n3 on eth0
-[t=3.000,src=n3] Receive 1 bytes on eth0
-[t=3.000,src=n3] Receive 1 bytes on eth0
-[t=3.000,src=n3] Receive 1 bytes on eth0
-[t=3.000,src=n3] Received: Hello World from 0!
-[t=3.000,src=n0] Send 2 bytes to n3 on eth0
-[t=3.000,src=n1] Send 1 bytes to n3 on eth0
-[t=3.000,src=n2] Send 1 bytes to n3 on eth0
-[t=3.000,src=n3] Received: Hello World from 1!
-[t=3.000,src=n3] Received: Hello World from 2!
-[t=6.000,src=n3] Receive 1 bytes on eth0
-[t=6.000,src=n3] Receive 1 bytes on eth0
-[t=6.000,src=n3] Received: Hello World from 1!
-[t=6.000,src=n3] Received: Hello World from 2!
-[t=7.000,src=n3] Receive 2 bytes on eth0
-[t=7.000,src=n3] Received: Hello World (2bytes) from 0!
-[t=7.000,src=n0] Send 2 bytes to n3 on eth0
-[t=7.000,src=n1] Send 2 bytes to n3 on eth0
-[t=7.000,src=n2] Send 1 bytes to n3 on eth0
-[t=10.000,src=n3] Receive 1 bytes on eth0
-[t=10.000,src=n3] Received: Hello World from 2!
-[t=12.000,src=n3] Receive 2 bytes on eth0
-[t=12.000,src=n3] Receive 2 bytes on eth0
-[t=12.000,src=n3] Received: Hello World (2bytes) from 0!
-[t=12.000,src=n0] Send 1 bytes to n3 on eth0
-[t=12.000,src=n1] Send 2 bytes to n3 on eth0
-[t=12.000,src=n2] Send 3 bytes to n3 on eth0
-[t=12.000,src=n3] Received: Hello World (2bytes) from 1!
-[t=15.000,src=n3] Receive 1 bytes on eth0
-[t=15.000,src=n3] Received: Hello World from 0!
-[t=17.000,src=n3] Receive 2 bytes on eth0
-[t=17.000,src=n3] Received: Hello World from 1!
-[t=18.000,src=n3] Receive 3 bytes on eth0
-[t=18.000,src=n3] Received: Hello World from 2!
-[t=18.000,src=n0] Send 5 bytes to n3 on eth0
-[t=23.000,src=n3] Receive 5 bytes on eth0
-[t=23.000,src=n3] Received: Hello World from 0!
+[t=0.000,src=n0,grp=def] Send 1 bytes to n3 on eth0
+[t=0.000,src=n1,grp=def] Send 1 bytes to n3 on eth0
+[t=0.000,src=n2,grp=def] Send 1 bytes to n3 on eth0
+[t=3.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=3.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=3.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=3.000,src=n3,grp=def] Received: Hello World from 0!
+[t=3.000,src=n0,grp=def] Send 2 bytes to n3 on eth0
+[t=3.000,src=n1,grp=def] Send 1 bytes to n3 on eth0
+[t=3.000,src=n2,grp=def] Send 1 bytes to n3 on eth0
+[t=3.000,src=n3,grp=def] Received: Hello World from 1!
+[t=3.000,src=n3,grp=def] Received: Hello World from 2!
+[t=6.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=6.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=6.000,src=n3,grp=def] Received: Hello World from 1!
+[t=6.000,src=n3,grp=def] Received: Hello World from 2!
+[t=7.000,src=n3,grp=def] Receive 2 bytes on eth0
+[t=7.000,src=n3,grp=def] Received: Hello World (2bytes) from 0!
+[t=7.000,src=n0,grp=def] Send 2 bytes to n3 on eth0
+[t=7.000,src=n1,grp=def] Send 2 bytes to n3 on eth0
+[t=7.000,src=n2,grp=def] Send 1 bytes to n3 on eth0
+[t=10.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=10.000,src=n3,grp=def] Received: Hello World from 2!
+[t=12.000,src=n3,grp=def] Receive 2 bytes on eth0
+[t=12.000,src=n3,grp=def] Receive 2 bytes on eth0
+[t=12.000,src=n3,grp=def] Received: Hello World (2bytes) from 0!
+[t=12.000,src=n0,grp=def] Send 1 bytes to n3 on eth0
+[t=12.000,src=n1,grp=def] Send 2 bytes to n3 on eth0
+[t=12.000,src=n2,grp=def] Send 3 bytes to n3 on eth0
+[t=12.000,src=n3,grp=def] Received: Hello World (2bytes) from 1!
+[t=15.000,src=n3,grp=def] Receive 1 bytes on eth0
+[t=15.000,src=n3,grp=def] Received: Hello World from 0!
+[t=17.000,src=n3,grp=def] Receive 2 bytes on eth0
+[t=17.000,src=n3,grp=def] Received: Hello World from 1!
+[t=18.000,src=n3,grp=def] Receive 3 bytes on eth0
+[t=18.000,src=n3,grp=def] Received: Hello World from 2!
+[t=18.000,src=n0,grp=def] Send 5 bytes to n3 on eth0
+[t=23.000,src=n3,grp=def] Receive 5 bytes on eth0
+[t=23.000,src=n3,grp=def] Received: Hello World from 0!
 [t=23.000,src=esds] Simulation ends
diff --git a/tests/api_send_wlan0_1s2r/out b/tests/api_send_wlan0_1s2r/out
index bb052dd..5fb7db3 100644
--- a/tests/api_send_wlan0_1s2r/out
+++ b/tests/api_send_wlan0_1s2r/out
@@ -1,16 +1,16 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
-[t=1.000,src=n1] Receive 1 bytes on wlan0
-[t=1.000,src=n2] Receive 1 bytes on wlan0
-[t=1.000,src=n1] Received: Hello World!
-[t=1.000,src=n2] Received: Hello World!
-[t=1.000,src=n2] Turned off
-[t=1.000,src=n0] Send 1 bytes on wlan0
-[t=2.000,src=n1] Receive 1 bytes on wlan0
-[t=2.000,src=n1] Received: Hello World!
-[t=2.000,src=n2] Turned on
-[t=2.000,src=n0] Send 1 bytes on wlan0
-[t=2.500,src=n2] Turned off
-[t=3.000,src=n1] Receive 1 bytes on wlan0
-[t=3.000,src=n1] Received: Hello World!
-[t=3.000,src=n2] Turned on
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n2,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n2,grp=def] Received: Hello World!
+[t=1.000,src=n2,grp=def] Turned off
+[t=1.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=2.000,src=n1,grp=def] Receive 1 bytes on wlan0
+[t=2.000,src=n1,grp=def] Received: Hello World!
+[t=2.000,src=n2,grp=def] Turned on
+[t=2.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=2.500,src=n2,grp=def] Turned off
+[t=3.000,src=n1,grp=def] Receive 1 bytes on wlan0
+[t=3.000,src=n1,grp=def] Received: Hello World!
+[t=3.000,src=n2,grp=def] Turned on
 [t=3.000,src=esds] Simulation ends
diff --git a/tests/api_send_wlan0_2s1r/out b/tests/api_send_wlan0_2s1r/out
index 788ee42..f9f2e96 100644
--- a/tests/api_send_wlan0_2s1r/out
+++ b/tests/api_send_wlan0_2s1r/out
@@ -1,6 +1,6 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
-[t=0.000,src=n1] Send 1 bytes on wlan0
-[t=0.000,src=n0] Interferences on wlan0
-[t=0.000,src=n1] Interferences on wlan0
-[t=0.000,src=n2] Interferences on wlan0
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=0.000,src=n1,grp=def] Send 1 bytes on wlan0
+[t=0.000,src=n0,grp=def] Interferences on wlan0
+[t=0.000,src=n1,grp=def] Interferences on wlan0
+[t=0.000,src=n2,grp=def] Interferences on wlan0
 [t=1.000,src=esds] Simulation ends
diff --git a/tests/api_sendt_eth0_1s1r/out b/tests/api_sendt_eth0_1s1r/out
index 254b865..0a5fb30 100644
--- a/tests/api_sendt_eth0_1s1r/out
+++ b/tests/api_sendt_eth0_1s1r/out
@@ -1,11 +1,11 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
-[t=1.000,src=n1] Receive 1 bytes on eth0
-[t=1.000,src=n0] Send worked!
-[t=1.000,src=n1] Received: Hello World!
-[t=1.000,src=n0] Send 1 bytes to n1 on eth0
-[t=1.500,src=n0] Send failed
-[t=1.500,src=n0] Send 1 bytes to n1 on eth0
-[t=2.500,src=n1] Receive 1 bytes on eth0
-[t=2.500,src=n0] Send worked!
-[t=2.500,src=n1] Received: Hello World!
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on eth0
+[t=1.000,src=n0,grp=def] Send worked!
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=1.500,src=n0,grp=def] Send failed
+[t=1.500,src=n0,grp=def] Send 1 bytes to n1 on eth0
+[t=2.500,src=n1,grp=def] Receive 1 bytes on eth0
+[t=2.500,src=n0,grp=def] Send worked!
+[t=2.500,src=n1,grp=def] Received: Hello World!
 [t=2.500,src=esds] Simulation ends
diff --git a/tests/api_sendt_wlan0_1s2r/out b/tests/api_sendt_wlan0_1s2r/out
index 9428958..33d4604 100644
--- a/tests/api_sendt_wlan0_1s2r/out
+++ b/tests/api_sendt_wlan0_1s2r/out
@@ -1,7 +1,7 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
-[t=1.000,src=n1] Receive 1 bytes on wlan0
-[t=1.000,src=n2] Receive 1 bytes on wlan0
-[t=1.000,src=n1] Received: Hello World!
-[t=1.000,src=n2] Received: Hello World!
-[t=1.000,src=n0] Send 1 bytes on wlan0
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=1.000,src=n1,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n2,grp=def] Receive 1 bytes on wlan0
+[t=1.000,src=n1,grp=def] Received: Hello World!
+[t=1.000,src=n2,grp=def] Received: Hello World!
+[t=1.000,src=n0,grp=def] Send 1 bytes on wlan0
 [t=1.500,src=esds] Simulation ends
diff --git a/tests/api_wait_2n/out b/tests/api_wait_2n/out
index 8a694cc..ab4bd2b 100644
--- a/tests/api_wait_2n/out
+++ b/tests/api_wait_2n/out
@@ -1,9 +1,9 @@
-[t=0.000,src=n0] Before wait
-[t=0.000,src=n1] Before wait
-[t=2.000,src=n0] After wait
-[t=2.000,src=n0] Before wait
-[t=2.000,src=n1] After wait
-[t=2.000,src=n1] Before wait
-[t=5.000,src=n0] After wait
-[t=5.000,src=n1] After wait
+[t=0.000,src=n0,grp=def] Before wait
+[t=0.000,src=n1,grp=def] Before wait
+[t=2.000,src=n0,grp=def] After wait
+[t=2.000,src=n0,grp=def] Before wait
+[t=2.000,src=n1,grp=def] After wait
+[t=2.000,src=n1,grp=def] Before wait
+[t=5.000,src=n0,grp=def] After wait
+[t=5.000,src=n1,grp=def] After wait
 [t=5.000,src=esds] Simulation ends
diff --git a/tests/api_wait_end_3n/out b/tests/api_wait_end_3n/out
index 54656da..40ed9f6 100644
--- a/tests/api_wait_end_3n/out
+++ b/tests/api_wait_end_3n/out
@@ -1,10 +1,10 @@
-[t=0.000,src=n0] Before wait for 0s
-[t=0.000,src=n0] First wait end
-[t=0.000,src=n1] Before wait for 1s
-[t=0.000,src=n2] Before wait for 2s
-[t=1.000,src=n1] First wait end
-[t=2.000,src=n2] First wait end
-[t=2.000,src=n0] Terminated
-[t=2.000,src=n1] Terminated
-[t=2.000,src=n2] Terminated
+[t=0.000,src=n0,grp=def] Before wait for 0s
+[t=0.000,src=n0,grp=def] First wait end
+[t=0.000,src=n1,grp=def] Before wait for 1s
+[t=0.000,src=n2,grp=def] Before wait for 2s
+[t=1.000,src=n1,grp=def] First wait end
+[t=2.000,src=n2,grp=def] First wait end
+[t=2.000,src=n0,grp=def] Terminated
+[t=2.000,src=n1,grp=def] Terminated
+[t=2.000,src=n2,grp=def] Terminated
 [t=2.000,src=esds] Simulation ends
diff --git a/tests/breakpoints_auto_1n/out b/tests/breakpoints_auto_1n/out
index e8fce88..41f8a73 100644
--- a/tests/breakpoints_auto_1n/out
+++ b/tests/breakpoints_auto_1n/out
@@ -1,9 +1,9 @@
-[t=0.000,src=n0] Send 5 bytes to n1 on eth0
+[t=0.000,src=n0,grp=def] Send 5 bytes to n1 on eth0
 [t=3.300,src=esds] Hello Callback!
 [t=6.600,src=esds] Hello Callback!
 [t=9.900,src=esds] Hello Callback!
 [t=13.200,src=esds] Hello Callback!
 [t=16.500,src=esds] Hello Callback!
 [t=19.800,src=esds] Hello Callback!
-[t=20.000,src=n1] Receive 5 bytes on eth0
+[t=20.000,src=n1,grp=def] Receive 5 bytes on eth0
 [t=20.000,src=esds] Simulation ends
diff --git a/tests/breakpoints_manual_1n/out b/tests/breakpoints_manual_1n/out
index 40c44b7..b7a6bc7 100644
--- a/tests/breakpoints_manual_1n/out
+++ b/tests/breakpoints_manual_1n/out
@@ -1,5 +1,5 @@
-[t=0.000,src=n0] Running
-[t=0.000,src=n1] Running
+[t=0.000,src=n0,grp=def] Running
+[t=0.000,src=n1,grp=def] Running
 [t=1.000,src=esds] Hello Callback!
 [t=2.000,src=esds] Hello Callback!
 [t=3.000,src=esds] Hello Callback!
diff --git a/tests/breakpoints_manual_no_callback_1n/out b/tests/breakpoints_manual_no_callback_1n/out
index defce2c..1debc22 100644
--- a/tests/breakpoints_manual_no_callback_1n/out
+++ b/tests/breakpoints_manual_no_callback_1n/out
@@ -1,3 +1,3 @@
-[t=0.000,src=n0] Running
-[t=0.000,src=n1] Running
+[t=0.000,src=n0,grp=def] Running
+[t=0.000,src=n1,grp=def] Running
 [t=10.000,src=esds] Simulation ends
diff --git a/tests/hidden_node_2s1r/out b/tests/hidden_node_2s1r/out
index 0922147..2b15788 100644
--- a/tests/hidden_node_2s1r/out
+++ b/tests/hidden_node_2s1r/out
@@ -1,4 +1,4 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
-[t=0.000,src=n2] Send 1 bytes on wlan0
-[t=0.000,src=n1] Interferences on wlan0
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
+[t=0.000,src=n2,grp=def] Send 1 bytes on wlan0
+[t=0.000,src=n1,grp=def] Interferences on wlan0
 [t=1.000,src=esds] Simulation ends
diff --git a/tests/mobility_eth0_bandwidth_1s1r/out b/tests/mobility_eth0_bandwidth_1s1r/out
index e0a3d04..b581084 100644
--- a/tests/mobility_eth0_bandwidth_1s1r/out
+++ b/tests/mobility_eth0_bandwidth_1s1r/out
@@ -1,4 +1,4 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
 [t=0.500,src=esds] Network update!
-[t=0.750,src=n1] Receive 1 bytes on eth0
+[t=0.750,src=n1,grp=def] Receive 1 bytes on eth0
 [t=0.750,src=esds] Simulation ends
diff --git a/tests/mobility_eth0_bandwidth_2s1r/out b/tests/mobility_eth0_bandwidth_2s1r/out
index 7138457..51bdb0b 100644
--- a/tests/mobility_eth0_bandwidth_2s1r/out
+++ b/tests/mobility_eth0_bandwidth_2s1r/out
@@ -1,6 +1,6 @@
-[t=0.000,src=n0] Send 1 bytes to n2 on eth0
-[t=0.000,src=n1] Send 1 bytes to n2 on eth0
+[t=0.000,src=n0,grp=def] Send 1 bytes to n2 on eth0
+[t=0.000,src=n1,grp=def] Send 1 bytes to n2 on eth0
 [t=1.000,src=esds] Network update!
-[t=1.500,src=n2] Receive 1 bytes on eth0
-[t=1.500,src=n2] Receive 1 bytes on eth0
+[t=1.500,src=n2,grp=def] Receive 1 bytes on eth0
+[t=1.500,src=n2,grp=def] Receive 1 bytes on eth0
 [t=1.500,src=esds] Simulation ends
diff --git a/tests/mobility_eth0_latency_1s1r/out b/tests/mobility_eth0_latency_1s1r/out
index ef56e0f..78f0a76 100644
--- a/tests/mobility_eth0_latency_1s1r/out
+++ b/tests/mobility_eth0_latency_1s1r/out
@@ -1,5 +1,5 @@
-[t=0.000,src=n0] Send 1 bytes to n1 on eth0
+[t=0.000,src=n0,grp=def] Send 1 bytes to n1 on eth0
 [t=0.500,src=esds] Network update!
 [t=1.000,src=esds] Network update!
-[t=1.333,src=n1] Receive 1 bytes on eth0
+[t=1.333,src=n1,grp=def] Receive 1 bytes on eth0
 [t=1.333,src=esds] Simulation ends
diff --git a/tests/mobility_eth0_latency_2s1r/out b/tests/mobility_eth0_latency_2s1r/out
index 41d59fc..fe63088 100644
--- a/tests/mobility_eth0_latency_2s1r/out
+++ b/tests/mobility_eth0_latency_2s1r/out
@@ -1,7 +1,7 @@
-[t=0.000,src=n0] Send 1 bytes to n2 on eth0
-[t=0.000,src=n1] Send 1 bytes to n2 on eth0
+[t=0.000,src=n0,grp=def] Send 1 bytes to n2 on eth0
+[t=0.000,src=n1,grp=def] Send 1 bytes to n2 on eth0
 [t=1.000,src=esds] Network update!
 [t=2.000,src=esds] Network update!
-[t=2.300,src=n2] Receive 1 bytes on eth0
-[t=2.300,src=n2] Receive 1 bytes on eth0
+[t=2.300,src=n2,grp=def] Receive 1 bytes on eth0
+[t=2.300,src=n2,grp=def] Receive 1 bytes on eth0
 [t=2.300,src=esds] Simulation ends
diff --git a/tests/mobility_wlan0_bandwidth_1s1r/out b/tests/mobility_wlan0_bandwidth_1s1r/out
index 95cdeeb..834fcf7 100644
--- a/tests/mobility_wlan0_bandwidth_1s1r/out
+++ b/tests/mobility_wlan0_bandwidth_1s1r/out
@@ -1,4 +1,4 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
 [t=0.500,src=esds] Network update!
-[t=0.750,src=n1] Receive 1 bytes on wlan0
+[t=0.750,src=n1,grp=def] Receive 1 bytes on wlan0
 [t=0.750,src=esds] Simulation ends
diff --git a/tests/mobility_wlan0_latency_1s1r/out b/tests/mobility_wlan0_latency_1s1r/out
index b1a2b0f..0da1c0f 100644
--- a/tests/mobility_wlan0_latency_1s1r/out
+++ b/tests/mobility_wlan0_latency_1s1r/out
@@ -1,5 +1,5 @@
-[t=0.000,src=n0] Send 1 bytes on wlan0
+[t=0.000,src=n0,grp=def] Send 1 bytes on wlan0
 [t=0.500,src=esds] Network update!
 [t=1.000,src=esds] Network update!
-[t=1.333,src=n1] Receive 1 bytes on wlan0
+[t=1.333,src=n1,grp=def] Receive 1 bytes on wlan0
 [t=1.333,src=esds] Simulation ends