OSI Model

jon boy

Hi Folks,

I am currently studying for the Security+ exam, and was just wondering if anyone could enlighten me on how much I really need to know about the OSI model in relation to the actual exam. I have reasonable knowledge of this, but some books have a chapter based on it, and some dont seem to mention it. Could it just be that you are expected to know about this as a pre-requisite??
Any response is appreciated, as security+ is my optional subject for the MCSA, so the sooner I get to grips with it the sooner I get a pay rise!!!

Cheers in advance

/usr

I'm not sure how much of it you really need to know for the exam.

How much do you know, exactly? You should know the different layers, what they do, and what items operate at each layer, in general.

jon boy

Thanks for the response /usr,

I understand the protocols and the layers at which they function pretty well, its just that using a variety of sources tends to lead to conflicting evidence; for example,the Microsoft Security+ guide stipulates that packet segmentation takes part at the network layer, when in fact it happens at the transport layer. Little quirks like this can get you into trouble if caution is thrown to the wind!!

Thanks again,

Jono

jdredd

I think you need to know what basic things function at what level, like what level does a router function at, IPSec , some of the other major applications and protocols, etc.

Ten9t6

The others are correct. You will need a basic understanding of which protocols and devices work at which layers. But, to make it easier on yourself for this test and future IT tests, I would learn everything you can about the OSI model. It will make life easier in the long run.

jon boy

Thanks for the response's folks....the thoughts are greatly appreciated.

qsub

I'm also studying for the security+ exam, and like the above said, you do need to know the basics. I can give you a straight example from the book. It says since the IP protocol isn't encrypted. By nature, it's a unsecure protocol because it doesn't provide anything that can protect the header that is added, therefore higher layer protocols are responsible for the encryption/secure transmission. Higher layer protocols like SSL, SSH.