Continued working on layer 2

1.txt

@@ -41,7 +41,8 @@ With all of that being said, let's jump straight in!
 
 PART 1
 
-Here we are, the physical layer! It's dark, dirty and grimy, and there's a distinct smell of solder in the air. It doesn't seem like much, but this, my friends, is where it all begins.
+Here we are, the physical layer! It's dark, dirty and grimy, and there's a distinct smell of solder in the air (I don't think they get many visitors).
+It doesn't seem like much, but this, my friends, is where it all begins.
 
 The physical layer is honestly the least 'networking-esque' of the layers. Think of it as the foundation for our OSI layer: data can't be transferred through networks, and indeed,
 networks wouldn't exist, if we didn't have the hardware to create them. The physical layer encompasses the actual cables and wires through which information flows. This is also where
@@ -106,5 +107,12 @@ Every manufacturer has an OUI assigned to them by the IEEE (Institute of Electri
 A simple Google search will provide you with this information.
 
 
-Now, let's tie this back into encapsulation. With every step in the encapsulation process (ie. with every layer that the data goes down), the layer adds relevant information to the data,
+Now, let's tie this back into encapsulation. With every step in the encapsulation process (ie. with every layer that the data goes down), that layer adds relevant information to the data,
 that will help the data be sent to the correct destination.
+
+So, when the data link layer (the second layer) receives data, in the form of a 'packet', from the third layer (we count the layers starting from the bottom), it adds certain information 
+to it as well. Specifically, it adds a header (which is inserted before the packet) and a trailer (which is inserted after the packet). 
+
+INSERT IMAGE HERE
+
+The header consists of four fields: