OSI Models - JuliaLightCNCS/Net-150 GitHub Wiki

09/02/22 OSI Models

OSI models go through 1 and 7.

1 physical - something you can touch - hub

2 data link - mac address - getting to the physical layer - switch

3 network - router - finding fastest routes - logical - changes - ip address

4 transport - opens doors(ports) between computers

5 session - opening different connectivity going on in the doors - extra links on websites

6 presentation - binary numbers tells computer what to open/show

7 application - user interface - shows user what they want to see

Acronyms:

All people seem to need data processing - going from 7-1

Please do not throw sausage pizza away - going from 1-7

Layers 5-7 are the software and getting the user what they want. Layers 1-4 do more of the hardware.

We also worked with command prompt to look at ip addresses. The first one we looked at was just ipconfig which got us basic information. Any information coming into the computer is going through the default gateway. Think of the default gateway is the receptionist for a hotel. The IPv4 is the individual room in said hotel.

The next thing we did was ipconfig /all got everything. Instead of just logical we got physical and logical as well. We got more information from ipconfig /all.

We proceeded to use ping. This command just tells the user whether something is on or not. After this we used tracert to look into the ping more. Trace route is what tracert means. tracert will tell you what in the route is on and what is off. Different routers are called hops which is what is looked at on pings and tracerts.

nslookup is what you use in command prompt to look at addresses and pathways for a website.

Commands used today(in order): ipconfig, ipconfig /all, ping, tracert, nslookup,

8 bits in a byte 48 bits in a hexadecimal

Mac (address): Media access control

CAM table: Is layer 2 because it has to do with switches.