IS-IS is very difficult

Last night I started reading about IS-IS and it is really really complicated.
Some I can understand like the Level1 ,2 ,1-2. CLNP, NSAP,NET,SNAP, difference between 10586 and RFC1195.

The difficult part is the content of the PDU. Do I need to know the TLV or memorize the code on the exam, and I don't know if I am correct if I am using ip on clns environment that I need to start 49 above AFI|IDI and if I am going to use clns routing I need to request. Anyway, any shorcut in this routing protocol, I didn't sleep last night and still here reading about IS-IS.

I watch the CBT nuggets and I can say that it helps me understanding IS-Is routing protocol. But Do I need to focus on the code and details of this routing protocol.

I found that sybex don't have much info not like cisco press or CCNP academy.

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Comments

blackzone

diffcult is one thing.

Knowing that you'll probably never use it and eventually forget but still have to learn is more frustrating.

JVE

I did not find this protocol as difficult as BGP, and unfortunately ISIS is gone from CCIE and is going away from CCNP in the new track, but BGP is here to stay. You dont need to know all those codes, just understand what makes up an area for the address, and what each type of router does. Dont panic on ISIS, you must not have gotten to BGP yet, or route maps and policies!

keenon

i would suggest learning the basics on isis but do everything to learn the bgp process

Ching01

I know a little bit on BGP (confederation,refelction, route maps , prefix list) but not yet try in my homelab and Dynamips.

I am just worry about IS-IS and really I only know the basic concept of IS-IS.

keenon

Ching01 wrote:

I know a little bit on BGP (confederation,refelction, route maps , prefix list) but not yet try in my homelab and Dynamips.

I am just worry about IS-IS and really I only know the basic concept of IS-IS.

if u know how it basically works and the addressing structure your fine

BUT YOU BETTER KNOW THAT BGP PATH SELECTION PROCESS

wildfire

I agree with Keenon dont get to hung up on ISIS, whilst you will undoutably get questions in the exam, you shouldnt expect the sort of depth you will get from OSPF/EIGRP and BGP. As Keenon said learn the path selection proccess and learn which belong to which group, ie well known mandatory, optional transative etc.

This should be a sufficient overview of ISIS

http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/osi_rout.htm

and

http://www.cisco.com/univercd/cc/td/doc/product/software/ios122/122cgcr/fipr_c/ipcprt2/1cfisis.htm

Ching01

No problem with OSPF and EIGRP for two weeks I focused on this routing protocols. Also about RIP and RIPv2 differences , it's very easy if you have a home lab you can see the difference and what is happening not like just reading a book and memorize.

Tha's why I am getting crazy with IS-IS anyway maybe I'll just continue reading and take some important information.

Thanks guys