Finding it really hard going with ISIS

aueddonline

I was wiZZing along with the BSCI and i've come to the ISIS chapter and my brain took one look at it and packed it's bags and walked out the door.

It seems to follow completely differnet logic to all the other protocols, maybe because of it's long history.

What i'm having the most trouble with is this level 0,1,2 and 3 and what they relate to, think that's where my confusion is starting.

Think this is a cry for help more than a question

Netstudent

I feel you bro. I just got done with a routing class in school that was kinda based off of BSCI. When we got to ISIS and BGP, i was like HUH?!?! I'm still at a CCNA level knowledge set, so those concepts are new to me. I think the hardest part about it is teaching it to yourself when it is that complicated.

It is completely different and it's like starting all over again. Take it slow and read repetively. Thats what I do when complicated concepts arise. I'v already dedicated myself to BCMSN though so I'm trying to wrap my brain around pVLAN, isolates and communities, primary, secondary.....It's like damn, does it ever stop? Just when you thought you had a pretty good understanding of something like VLANS, NP comes along and shuts you up.

rakem

aueddonline wrote:

I was wiZZing along with the BSCI and i've come to the ISIS chapter and my brain took one look at it and packed it's bags and walked out the door.



What i'm having the most trouble with is this level 0,1,2 and 3 and what they relate to, think that's where my confusion is starting.

Think this is a cry for help more than a question

i know what you mean.... im also studying for BSCI and ISIS had me pretty confused for a bit... all this CLNS crap... i didn't have a clue about any of it... my approach though was just to start muck around configuring it so i could see how it actually worked, after i saw how it worked understanding the theory wasn't to difficult. For BSCI i think you really only need to worry about level 1 and level 2.

so maybe get start playing round with the configuration of ISIS, do some labs and stuff and you will get the hang of it...

aueddonline

Netstudent wrote:

It is completely different and it's like starting all over again.

Thoughts straight out of my own head man.

Both giving good advise though, might configure something today get picture in my head going on.

networker050184

I agree ISIS is odd when first starting. I think they already gave the best advice, get someequipment and just go at it with the ? for a while to get a feel of the commands.

Aquabat [banned]

o god i am scarred, this is why i'm doing bsci second

cisco_trouble

Yeah, ISIS can be a bit over one's head, but after a while you realise its just a "virtual" hierachical version of OSPF. Meaning that it doesn't require and area0 or transit area as a backbone. Oh yes, and it works on layer 2, encapsulated directly into the frame...hence the CLNS confusion...
The different levels just refer to the different capabilities i.e. routing. Like with OSPF you had the different LSAs per area type (standard, backbone,stubby, totally stubb, NSSA); similar with the levels in ISIS.

level0-pc-router
level1-router-router(intra area)
level1/2-(inter area)
level3(inter domain)..if i can put it like this

and the tags which relate to each of them...IIS,ES-IS,IS-IS...

And don't worry, the exam isnt as scary as the amount of work...ONT is bugging me...i hate memorizing facts...

Does anyone know if there are any sims in the ONT exam?