diff --git a/School/Analyse/Layers/3. Network Layer.md b/School/Analyse/Layers/3. Network Layer.md
index 6998470..13d99ca 100644
--- a/School/Analyse/Layers/3. Network Layer.md	
+++ b/School/Analyse/Layers/3. Network Layer.md	
@@ -110,3 +110,8 @@ Example 144.24.13.172/**20 (20 bits used for network ID)**
 ### Exceptions in IPV4
 ![[exceptions-ipv4.png]]
 
+Also the following addresses are not used as a valid and unique IPv4 Addresses:
+
+10.0.0.0 - 10.255.255.255/8 (16.777.216 hosts)
+172.
+