Computer Networking Question(s)

[vincin]

Im in a computer networking class and need some explanations of things if anyone knows alot about networking. Okay, in the OSI model, I get the 7 layers....and each layer has certain functions right? well why do some layers repeat those tasks...like flow control, encryption. do packets turn into frames..that turn into bits???
whats packet sniffing? is there frame sniffing? bit sniffing??? SPDU sniffing!?!?

Why are the first 3 layers apart of the 'subnet' and not the other layers.

Whats the freaking purpose of the session and presentation layer?! they suck.

Wheres the "medium access layer" in the OSI model? data-link?? and whats the big deal about medium access...its boring.

Whats the point of token ring? it seems slow and pointless.

I just need a detailed explanation of this stuff from a computer expert. I understand programming, but networking seems like another system.

[Japan]

Sorry guy I don't know how to help you...or do I? by japan

[Chanus]

The Tolkein ring was meant to bind all the nine kings together under the rule of Sauron.

It seems slow and pointless because it was written in the '30s.

[Crone]

Im in a computer networking class and need some explanations of things if anyone knows alot about networking. Okay, in the OSI model, I get the 7 layers....and each layer has certain functions right? well why do some layers repeat those tasks...like flow control, encryption. do packets turn into frames..that turn into bits???
whats packet sniffing? is there frame sniffing? bit sniffing??? SPDU sniffing!?!?

Why are the first 3 layers apart of the 'subnet' and not the other layers.

Whats the freaking purpose of the session and presentation layer?! they suck.

Wheres the "medium access layer" in the OSI model? data-link?? and whats the big deal about medium access...its boring.

Whats the point of token ring? it seems slow and pointless.

I just need a detailed explanation of this stuff from a computer expert. I understand programming, but networking seems like another system.

You understand programming but don't know how to use Google?

[vincin]

ive read a lot on google and it still isnt clicking in my tiny brain.

[vincin]

haha

[psicore]

I could reply to each of the questions, but since your a programmer. I would reccommend reading a Network + book. They are cheap and will answer any of your questions.

If the above questions are for specific reasons, let me know I can add further detail. The range of questions above could take a bit to answer if the fundamentals of networking is not understood.

[Cyrius]

http://en.wikipedia.org/wiki/OSI_model

[vincin]

your right, i do need to read more books. Im just too lazy. Ill get on that. finals are coming up and I think this class might be the only one that isnt an A for me. All I have to say is that I underestimated those networking guys, that stuff is hard!

[vincin]

@ Cyrius. Ive read that part of the OSI model. I just dont get how each layer works together to form a message. Cuz we just learned that Bridges are for layer 2 data, and routers are for layer 3 data....so each layer is sent seperatly?

[Kava]

Yay CompTIA. Are you going for your A+ or Network + certification? Lots of easy to read and easy to find info on CompTIA's website.

And alot of that stuff is redundant, and old, and not really used, but they like to teach it so that they can move you on to the next stuff.

Hands on experience will always beat out book smarts with networking and pc tech stuff, unfotunately companies wanna see those certs before giving you an opportunity to use your hands.

Good luck!

[vincin]

Thanks Kava! Im just on my last year in Computer Science. I chose networking as an elective, which is harder than I thought.

[odizzido]

Sounds like the OSI model is just confusing you. Honestly if you just look at how things work and ignore the stupid OSI model it might be a lot easier for you. I only learned OSI stuff for tests.

and no it's not all sent separately. you pretty much need "layer 2/3" info to send a packet anywhere and they need to be together.

[President]

The model doesn't make sense for shit. Get real world experience.

[Lazortag]

@ Cyrius. Ive read that part of the OSI model. I just dont get how each layer works together to form a message. Cuz we just learned that Bridges are for layer 2 data, and routers are for layer 3 data....so each layer is sent seperatly?

..Or is it?

[Itchybottom]

The OSI model, and it's sub-layers make perfect sense for those that need to reference it. It's not all that confusing, but you need to expand it and re-organize it in your head after you learn about encapsulation and routing procedures. You also need to throw away a lot of what you've learned if you stick to brand specific hardware (such as Cisco using IS-IS over IDRP a while ago) What's going to be REALLY confusing, is when IPV6 becomes more widely used, it's going to be war of VTI vs EOIP vs zero index GRE for the first few years due to people not wanting to spend the money to update their networks.

Most of the time though, in the case of datacenter work, the only layers you need to concern yourself with are 2 and 7.

As far as needing a certification to get your foot in the door -- be more aggressive. Don't send your CV to human resources, you aren't just a piece of paper in a stack; research the company and get it on the appropriate desk if you think you're technically suited for the job. Everyone likes free lunch too, so if you do something like attach a note to your cover letter saying you want to discuss the company further -- you just might get a sit down over the braindead that think there is still a rule system in place for business etiquette. Chances are in the IT field (network engineering and systems analyst especially) that person in question is going to be more willing to get you hired, than the Net+ certified idiots they are forced to babysit all day. A lot of companies are really just looking for college degrees because you're showing that you can stick with something -- after all, highschool was your first job and your choices after that reflect greatly on how you view the world.