Taking a net+ class

[linkstojustice]

And they saved the best for last. Finally getting into the good stuff, network security. :D

[Sitwon]

You should follow up Net+ with CCNA before moving on to Linux+ and Security+. CCNA will go much more in-depth with the OSI model.

I find a lot of people seem to lack the solid foundation in understanding the OSI model and how each layer works. As a result, they're ill-equipped to speak intelligently about network architecture, efficiency, and security.

[murder_face]

The OSI model has always been my downfall. I couldn't remeber it right now if you paid me. I forget where, I think maybe slashdot, but there was a debate on the importance of the OSI model in general. If memory serves me(for a change) i think it was 50/50 on the importance of it....

You should follow up Net+ with CCNA before moving on to Linux+ and Security+. CCNA will go much more in-depth with the OSI model.

I find a lot of people seem to lack the solid foundation in understanding the OSI model and how each layer works. As a result, they're ill-equipped to speak intelligently about network architecture, efficiency, and security.

[digip]

Only things I ever really paid attention to were layers 2 and 3, and what that means for networking in general, IP vs MAC address connectivity and NAT, etc. I'd have to refresh myself on the layers, but for the most part, you only ever really work with 1-3 when setting up networks, while most of the upper stuff is all session, protocols, and application layer stuff. Its just good to know it for general understanding of routing and internetworking in general, but for the most part, you aren't consciously thinking about most of it when you are just setting up your lan unless you have specific routing, segmentation, and security needs, such as routing protocols, vlans, routing table exchanges, and setting up access control lists, which all of that will be in your cisco class if you take one. Personally, I loved the cisco stuff, and just down right hated all the Microsoft classes. I'd much rather setup the physical network hardware and topology, than be an Active Directory or Domain Admin, or for fucks sake, be an Exchange server admin. God how I hated exchange, and we never even finished it in class, only touched upon it since 2003 was changing over to 2008 and most of it was two part, gui and power shell stuff to complete setup. Most retarded shit I ever dealt with.

[Sitwon]

The OSI model has always been my downfall. I couldn't remeber it right now if you paid me. I forget where, I think maybe slashdot, but there was a debate on the importance of the OSI model in general. If memory serves me(for a change) i think it was 50/50 on the importance of it....

Whether or not the OSI model is a good model for describing or teaching networking is sort of irrelevant. The point is understanding the tools and technologies at every layer of the stack, regardless of which method you use to model/organize the stack.

OSI layers 1-3 are pretty solid.

Layer 1 is the physical medium. Whether wired or wireless. Understanding details about how messages are physically modulated, demodulated, or otherwise communicated between end points is key to understanding why different types of cabling, antennas or distances can matter.

Layer 2 is the data-link layer. This is where MAC addresses come into play. Each device on the physical network needs some form of universally unique ID value to distinguish it from other devices, even in the absence of any higher-level configuration.

Layer 3 is the network layer. This is where you get a routable address such as an IPv4 or IPv6 address. The important thing here is that your routable address, unlike your MAC address, is not random. At least some of the bits which make up the address are significant in that they specify your logical position on the network (which may or may not have any correspondence to your physical location). It allows routing algorithms and devices to build routing tables and decide which direction to send packets addressed to you, even if they don't know exactly where you are or even if you exist. Understanding how routable addresses work, and the resulting netmasks and routing tables, is crucial to developing or profiling network topologies.

Layers 4-6 are somewhat academic unless you're working with different packet protocols. The TCP/IP model bundles them together into the generic "transport layer". There are some useful traits and features in these layers that are worth knowing about, but generally speaking the interesting part is learning about the protocols themselves at these layers, not the layers themselves which are arguably a poor abstraction. (This is where you do TCP session hi-jacking, for instance.)

Layer 7 is more about the high-level protocols that applications speak to each other over top of the network (but could presumably be spoken over any network using any kind of addressing or transport so long as the contents of the messages are delivered intact).

[badbass]

Ip addressing is a good thing to learn about. This will help you. Cisco, subnet masking, vlsm, ipv6. I dont know if they go into vlans, but this is more of a cisco voip thing. Cisco will talk about packet headers. Types of network cabling and how they work. I can go on and on but I wont.

[linkstojustice]

Whether or not the OSI model is a good model for describing or teaching networking is sort of irrelevant. The point is understanding the tools and technologies at every layer of the stack, regardless of which method you use to model/organize the stack.

Thanks for the feedback, I have my final for the class this week so ive been going through everything. I'm going for a quick AAS in programming so I don't think I will get into taking any cisco classes higher then maybe the introduction. Next semester I'm taking IT essentials, and introduction to linux(stupid pre requisites), along with some of the general classes I need

Edited December 7, 2012 by linkstojustice