diff --git a/.obsidian/workspace b/.obsidian/workspace
index 3a2e8c0..62338f8 100644
--- a/.obsidian/workspace
+++ b/.obsidian/workspace
@@ -88,6 +88,7 @@
   "active": "bc6e8ad9aa0f44c3",
   "lastOpenFiles": [
     "School/Analyse/Layers/2. Datalink Layer.md",
+    "School/Analyse/Network Types.md",
     "School/Analyse/Images/distortion.png",
     "School/Analyse/Images/noise-signal.png",
     "README.md",
@@ -95,7 +96,6 @@
     "School/Analyse/Layers/4. Transport Layer.md",
     "School/Analyse/Layers/1. Physical Layer.md",
     "School/Analyse/Comminucation Mediums.md",
-    "School/Analyse/Images/modulation-amplitude.png",
-    "School/Analyse/Images/modulation-phase-2.png"
+    "School/Analyse/Images/modulation-amplitude.png"
   ]
 }
\ No newline at end of file
diff --git a/School/Analyse/Images/ethernet-frame.png b/School/Analyse/Images/ethernet-frame.png
new file mode 100644
index 0000000..017a5a8
Binary files /dev/null and b/School/Analyse/Images/ethernet-frame.png differ
diff --git a/School/Analyse/Layers/2. Datalink Layer.md b/School/Analyse/Layers/2. Datalink Layer.md
index a0fef82..698647f 100644
--- a/School/Analyse/Layers/2. Datalink Layer.md	
+++ b/School/Analyse/Layers/2. Datalink Layer.md	
@@ -5,7 +5,7 @@ The Data Link Layer also splits up packets into smaller chunks called a frame. T
 
 Like the Network Layer the Data Link Layer is also responsible for flow control and error checking.
 
-## Error detection
+## Error Detection
 Transmissions are not always error free. In case of an error, it should be detected and the message should be re transmitted (whenever possible)
 
 Detecting errors are handled by different algorithms:
@@ -18,6 +18,17 @@ Data is split up in smaller chunks called frames. For each frame we add some ext
 - Who is sender?
 - Who is receiver?
 - Length of chunk
-- Type of chunk (normal message, error me)
+- Type of chunk (normal message, error message, control message)
 - Error checking values (ex. CRC code)
-- Data and metadata are put in single message called frame
\ No newline at end of file
+- Data and metadata are put in single message called frame
+
+## Ethernet Protocol
+Ethernet is a protocol used at the data link layer of wired networks.
+
+Ethernet uses specific hardware addresses to identify hosts on a network.
+These 6-byte-integer addresses are names Medium Access Control (MAC Address)
+
+Ethernet frame has the following format:
+![[ethernet-frame.png]]
+
+## Wireless networks