diff --git a/squinnondation/hazel.py b/squinnondation/hazel.py
index db99db9..3a531d5 100644
--- a/squinnondation/hazel.py
+++ b/squinnondation/hazel.py
@@ -68,18 +68,37 @@ class Squirrel(Hazelnut):
         curses.init_color(curses.COLOR_WHITE, 1000, 1000, 1000)
         for i in range(curses.COLOR_BLACK + 1, curses.COLOR_WHITE):
             curses.init_pair(i + 1, i, curses.COLOR_BLACK)
-
-        self.hazelnuts = dict()
+        
+        #dictionnaries of neighbours
+        self.potentialhazelnuts = dict()
+        self.activehazelnuts = dict() #of the form [hazelnut, time of last
+        #hello, time of last long hello, is symetric]
         self.add_system_message(f"Listening on {self.address}:{self.port}")
-
+    
+    def new_hazel(self, address: IPv6Address, port: int) -> Hazelnut:
+        """
+        Returns a new hazelnut (with no id nor nickname)
+        """
+        hazelnut = Hazelnut(address=address, port=port)
+        return hazelnut
+    
+    def is_active(self, hazel: Hazelnut) -> bool :
+        return (hazel.address, hazel.port) in self.activehazelnuts
+    
+    def is_potential(self, hazel: Hazelnut) -> bool :
+        return (hazel.address, hazel.port) in self.potentialhazelnuts
+    
+    def remove_from_potential(self, address: IPv6Address, port: int)-> None:
+        self.potentialhazelnuts.pop((address, port), None)
+    
     def find_hazelnut(self, address: str, port: int) -> Hazelnut:
         """
-        Translate an address into a hazelnut, and store it in the list of the hazelnuts, ie. the neighbours.
+        Translate an address into a hazelnut. If this hazelnut does not exist,
+        creates a new hazelnut.
         """
-        if (address, port) in self.hazelnuts:
-            return self.hazelnuts[(address, port)]
+        if (address, port) in self.activehazelnuts:
+            return self.activehazelnuts[(address, port)][0]
         hazelnut = Hazelnut(address=address, port=port)
-        self.hazelnuts[(address, port)] = hazelnut
         return hazelnut
 
     def send_packet(self, client: Hazelnut, pkt: Packet) -> int:
@@ -205,7 +224,7 @@ class Squirrel(Hazelnut):
         self.add_message(msg)
 
         pkt = Packet.construct(DataTLV.construct(msg, self))
-        for hazelnut in list(self.hazelnuts.values()):
+        for hazelnut in list(self.activehazelnuts.values()):
             self.send_packet(hazelnut, pkt)
 
     def handle_mouse_click(self, y: int, x: int, attr: int) -> None:
diff --git a/squinnondation/messages.py b/squinnondation/messages.py
index 5ad2886..051ab58 100644
--- a/squinnondation/messages.py
+++ b/squinnondation/messages.py
@@ -6,6 +6,7 @@ from ipaddress import IPv6Address
 from enum import Enum
 import socket
 import sys
+import time
 
 
 class TLV:
@@ -143,7 +144,20 @@ class HelloTLV(TLV):
         return data
 
     def handle(self, squirrel: Any, sender: Any) -> None:
-        # TODO Implement HelloTLV
+        timeH = time.time()
+        timeHL = None
+        if not squirrel.is_active(sender) :
+            sender.id = source_id #The sender we are given misses an id
+        else :
+            timeHL = squirrel.activehazelnuts[(sender.address, sender.port)]
+        if self.is_long and dest_id == squirrel.id :
+            timeHL = time.time()
+        #elif source_id != sender.id :
+            #That neighbour is lying about its ID
+        squirrel.remove_from_potential(sender.address, sender.port)
+        
+        squirrel.activehazelnuts[(sender.address, sender.port)] = [sender, timeH,\
+                                                                   timeHL, True]
         squirrel.add_system_message("Aaaawwww, someone spoke to me and said me Hello smiling_face_with_"
                                     + (":3_hearts:" if self.is_long else "smiling_eyes:"))
 
@@ -171,9 +185,9 @@ class NeighbourTLV(TLV):
             self.port.to_bytes(2, sys.byteorder)
 
     def handle(self, squirrel: Any, sender: Any) -> None:
-        # TODO Implement NeighbourTLV
-        squirrel.add_system_message("I have a friend!")
-        squirrel.add_system_message(f"Welcome {self.ip_address}:{self.port}!")
+        if not (ip_address,port) in squirrel.activehazelnuts and not (ip_address,port) in squirrel.potentialhazelnuts:
+            squirrel.potentialhazelnuts[(ip_address, port)] = squirrel.new_hazel(ip_address, port)
+        squirrel.add_system_message(f"New potential friend {self.ip_address}:{self.port}!")
 
 
 class DataTLV(TLV):
@@ -301,9 +315,10 @@ class GoAwayTLV(TLV):
             self.message.encode("UTF-8")[:self.length - 1]
 
     def handle(self, squirrel: Any, sender: Any) -> None:
-        # TODO Implement GoAwayTLV
-        squirrel.add_system_message("Some told me that he went away. That's not very nice :( "
-                                    "I should send him some cake.")
+        if squirrel.is_active(sender) :
+            squirrel.activehazelnuts.pop((sender.addess, sender.port))
+            squirrel.potentialhazelnuts[(sender.address, sender.port)] = sender
+        squirrel.add_system_message("Some told me that he went away : "+message)
 
 
 class WarningTLV(TLV):
diff --git a/squinnondation/squinnondation.py b/squinnondation/squinnondation.py
index 1769fbb..c1f900b 100644
--- a/squinnondation/squinnondation.py
+++ b/squinnondation/squinnondation.py
@@ -74,7 +74,7 @@ class Squinnondation:
 
             if instance.args.client_address and instance.args.client_port:
                 hazelnut = Hazelnut(address=instance.args.client_address, port=instance.args.client_port)
-                squirrel.hazelnuts[(instance.args.client_address, instance.args.client_port)] = hazelnut
+                squirrel.activehazelnuts[(instance.args.client_address, instance.args.client_port)] = hazelnut
 
             Worm(squirrel).start()
             squirrel.wait_for_key()