NAT Terms

hardstylewon

Hey everyone. I am scheduled for the CCENT this friday and I just can't wrap my mind around these NAT Terms.

Outside Local, Outside Global, Inside Local, Inside Global.

Does anyone have a good way to explain this or a easy way to remember? I read odoms ICND1 book and Exam Prep CCENT and I thought I had it before but i've been moving a lot due to the military and had to reschedule for a later date. I am using Boson's exam prep. Thanks ahead of time!

-hardstyle

vinbuck

The first thing you need to wrap your head around is Cisco's terminology. Inside is not always a private IP and Outside is not always a public IP. They refer more to the direction of the translation...inbound vs outbound

Here is how I remember them and it seems to work well.

Inside - Anything originating from inside the Local LAN and destined out to the Internet (This means NAT translates only in that direction)

Outside - Anything originating from the outside interface that requires access to IP that is on the Inside LAN (Commonly referred to as NAT pinhole in SOHO routers)

This will get a host on the inside LAN out to the Internet

Inside Local - 192.168.1.1
Inside Global - 125.25.25.1

This will get a host on the internet to a service hosted on the private LAN

Outside Local - 192.168.1.1
Outside Global - 125.25.25.1

docrice

If you don't pick up these terms easily, don't feel alone - a lot of people seem to stumble on this. I don't really hear these referenced outside of the CCNA. I work a lot on ASAs and even there I don't see these terms used.

hardstylewon

vinbuck wrote: »

The first thing you need to wrap your head around is Cisco's terminology. Inside is not always a private IP and Outside is not always a public IP. They refer more to the direction of the translation...inbound vs outbound

Here is how I remember them and it seems to work well.

Inside - Anything originating from inside the Local LAN and destined out to the Internet (This means NAT translates only in that direction)

Outside - Anything originating from the outside interface that requires access to IP that is on the Inside LAN (Commonly referred to as NAT pinhole in SOHO routers)

This will get a host on the inside LAN out to the Internet

Inside Local - 192.168.1.1
Inside Global - 125.25.25.1

This will get a host on the internet to a service hosted on the private LAN

Outside Local - 192.168.1.1
Outside Global - 125.25.25.1

I got it I re read some stuff and got ahold of it. I learned it easily before but had a few months off doing pre deployment and stuff with leaving the army. Thanks.

docrice wrote: »

If you don't pick up these terms easily, don't feel alone - a lot of people seem to stumble on this. I don't really hear these referenced outside of the CCNA. I work a lot on ASAs and even there I don't see these terms used.

Yea I got it. Thanks for the support. I worked as a network technician at a hospital and didnt hear them either.

oli356

I also didn't quite get these terms, on the Cisco academy there is about 8 of them though! I can't remember what the others were.. same things just in different orders.