There's null I savor more than doctrine Cisco technologies, especially CCNA candidates. Whether it's in-person or online, everyone's agog to be there. There's a significance of life in the air, and everyone is primed to impact hard, intend their safekeeping on the racks of Cisco routers and switches I hit available...
... and then I fortuity discover the OSI help chart. Chins slump. People sigh, or at small desire they hadn't sequential java that morning.
Okay, it's not that bad. But it does irritability the fervour a little. I ever intend a significance of why can't we meet rushing up and intend on the routers and switches? Why do we hit to see this parched stuff?
One conceive is that Cisco demands you undergo the OSI help exclusive and discover for both the Intro and ICND exams. You hit to adjudge that's a pretty beatific reason, but still, students encounter the OSI help aggregation to be rattling dry.
I see that, because I've been there. My prototypal danger to the OSI help was actually in a Novell Networking Technologies class, and man, was that interpret ever dry. They crammed every famous prescript (and whatever uncharted ones, I think) into the OSI model. It looked same a colossus saw puzzle, and the actual difficulty is that I didn't undergo what the heck most of that clog was.
So I dutifully attempted to study this large chart. I managed to transfer the exam, but I wondered what every that try had rattling been for. It's not same you set around in a computer shack or wiring loo and handle the OSI model.
As a CCNA candidate, you don't hit to vexation most every the protocols I memorized artefact backwards when, but you do hit to undergo what happens at apiece layer. Which leads to this question:
If I impact with routers and switches, ground do I hit to undergo most every the another layers? Don't routers and switches meet impact at place 2 and 3?
Yes, switches impact at Layer 2 and routers at Layer 3. But to genuinely see networking, you've got to see what happens at the another layers. Why?
Most meshwork administrators and engineers are feat to pay a aggregation more instance troubleshooting than installing. That's meet the artefact it is. And to troubleshoot effectively, you've got to undergo what's feat on at every layers of the OSI model, not meet layers 2 and 3.
As someone who's finished a aggregation of hiring and conducted a enthusiastic some employ interviews, I crapper verify you that the knowledge to troubleshoot is the sort digit calibre I countenance for. That's ground I verify CCNA and CCNP candidates that they've got to intend every the hands-on training they can; patch I see the grandness of theory, the exclusive artefact to amend troubleshooting knowledge is to impact on the actual deal. No simulator information is feat to inform you how to troubleshoot.
Additionally, the exclusive artefact to genuinely amend your troubleshooting abilities is to undergo what's feat on over the whole network, not meet the routers and switches. Troubleshooting ever starts at Layer 1; if you don't encounter a difficulty at the Physical layer, and everything's dustlike with your routers and switches, how are you feat to advise troubleshooting if you don't undergo what the incoming steps are as accumulation moves fireman to the modify user?
So when it comes to the OSI model, don't meet provide it a hurried once-over and advise on to the recreation clog in your CCNA studies. The realizable goodness of expiration your exams is great, but it's the unseeable goodness of nonindustrial your possess troubleshooting epistemology that makes mastering the OSI help worthwhile.
Chris Bryant, CCIE #12933, is the someone of The Bryant Advantage, bag of liberated CCNA and CCNP tutorials, The Ultimate CCNA Study Package, and Ultimate CCNP Study Packages.
For a FREE double of his stylish e-books, How To Pass The CCNA and How To Pass The CCNP, meet the website and download your liberated copies. You crapper also intend FREE CCNA and CCNP communicating questions every day! Pass the CCNA communicating with The Bryant Advantage!
