Networking and the OSI Model - digg this
Since things are a little slow today I decided to "hit the books". My contracting agency has an online training suite. I've been working on the CompTIA Security+ cert and today I started the Network+ track in addition. It just went over the OSI model. In an effort to see how well I understand what I just heard I am going to reproduce it (more or less and in my own words) below. Feel free to critique (those two of you that understand this sort of thing).
If you enjoyed this entry subscribe to this blog by email or feed readerPhysical - This is where the 1s and 0s happen. This is also where you're talking about the actual physical connection (RJ-45).
Data Link - Packets are put together on this layer. This is also the layer where MAC addresses get assigned/translated.
Network - This layer gets those packets out there. Routers use this layer and it's this layer that's responsible for making sure that different kinds of networks can talk to each other.
Transport - Handshakes happen here. The packet goes up to its new home and makes sure that it's in the right place. It might then send back confirmation (connection oriented) or if that isn't necessary then it just sets up residence (connectionless).
Session - The Session layer makes sure that the packets are sent to the right place in its new host. The instructor calls this layer a traffic cop. I think of the flight controller with its two little cones. Here is where port numbers and sockets play some sort of role (I'm a little fuzzy there).
Presentation - Now that the packets are in their new home and in the right room so to speak, it is this layer that begins to reassemble them. Here they are decompressed unencrypted (or compressed and encrypted if the packet is going out).
Application - This layer is not the software itself but is the "hook" that the software (web browser, ftp software) uses to connect to the network.
Feel free to give my any better analogies/descriptions that you have.
Total Number of Comments: 1
You forgot the part where the Network Admin says the magic words.