How do I know if I have a technical understanding of TCP/IP networking and network architecture?

I am considering taking a snort class, but they require I have technical understanding of TCP/IP networking and network architecture.

I have some experience with IPtables, not much, some experience with tcpdump, some experience with cisco switches, and some experience with configuring 3rd party firewall software (like the APF) for ingress/egress traffic by port and/or ip. I would say I'm at the beginner level of those, execpt for tcpdump and configuring 3rd party firewall which I am intermeidate.

Does that qualify as a "technical understanding".

if you do honestly understand tcpdump output then that's probably a good yardstick. with more information it might be clearer but i'd say you should...

- know the osi model
- know the tcp/ip model
- be able to compare the above matching up each layer
- compare tcp and udp
- understand arp
- appreciate relationships between each model layer and the realities of encapsulation

but if you're the sort of person who can appreciate things without necessarily already knowing them, then you can probably fill in the gaps yourself as you go along.

Obviously prereqs vary hugely, but i would think that for snort you could well go into quite a bit of theory in order to make the practical make sense, and lots of snort checks are analysing the health of the network packets themselves, not just the data contents.

I'd say if you comfortably understand the information required to pass the Cisco ICND course (Minus the Cisco specific commands) you should have a decent understanding of TCP/IP and networking. (addressing, Routing, Subnetting, NAT, etc.. )

Do you understand the OSI network Model ?
Do you understand the TCP/IP Network Model ?
I would imagine there would be quite a few concepts from those models referenced in an IDS course.

you didn't know what pcap was though ;-)

since i am learning about tcp/ip and i find this website to be the best..

http://www.linuxhomenetworking.com/w..._to_Networking

Gratsi!