How NAT works

From source to destination, how NAT translated the private address to a public one.

[mohamedyoussuf]

Wobderful explanation. This video helped me a lot. Thank u for sharing

[TrevorKevorson]

Great video, I'm currently revising for an exam in a fortnight and couldn't remember all the terms used by Cisco, this really helped my understanding (I had an idea how NAT worked but couldn't remember the difference between inside global and outside global). I really liked that the video was bite sized, and the analogy used was pretty good, I just hope I remember little slugger when it comes to exam time :-)

[vblacktanonymous]

Great Explanation! Hope you make more of this types of video in the future.

[timmotube]

before i could understand the concept of NAT with my teacher but your video benefit me so much thank you and hop to get more video

[vidushikulshrestha]

thankyou ma'am, this video has really helped me to understand NAT....

[ambientmelancholy]

The part where I kept confusing myself was the perspective aspect of this process. As soon as the packet leaves from its source LAN, traverses across the WAN and enters the ingress interface of the router connected to the packet's destination LAN... I kept switching from the perspective of the original source LAN to the destination LAN's perspective, instead of keeping my focus on the packet's source LAN's perspective for the entire journey of the packet (using ICMP echo request/echo reply) ... If that makes any sense. Seeing your illustrations helped put everything.. Into the correct perspective lol.

[clockwise]

aunt claire trying to explain to little slugger why he didnt get a letter back

[ramsrinivasan]

Beautiful explanation. Now I got it. No one could explain this to me before - not even the greatest instructors.
Thank you Kim!

[yiannisserpico]

Outside local and Outside global are the same because we are talking about a not private IP address destination. If destination IP was in RFC 1918 private IP ranges, another translation would take place in outside global to outside local border. Am I correct? Thank you!

[nusstu]

Did she say little slugger? Can someone explain what's that cuz where I come from we don't use it.

[LTVoyager]

This discusses what NAT does, but not how it works. How does it translate the private address to the public address? That is how it works.

[DerpyNetworking]

What happened to your channel? I would love to see more videos!

[Kozo]

But how does the R2 know how to route when packets are coming from Internet?
If instead of PC1, we would have PC1, PC2, ..., PC10, all talking with the same Web Server, how would R2 know to route the responses back to the corresponding PCx?

[sportalero]

Now THAT was easy to understand. I mean, I understood how NAT worked but kept getting crossed up at Outside Local and Outside Global. I see now that they'll always be the same identical destination IP, yet my study guides wont just come out and say that. In fact, OUTSIDE LOCAL - This is usually the address of the router interface connected to the ISP. What,  my Border Router interface connected to the ISP? Wouldn't that be the Inside Global IP? Are they referring to the router interface that my Destination sits behind that connects to the ISP? Why not just say OUTSIDE LOCAL - Destination IP?

[RIcYanng]

I would say that inside means source, and outside means destination.

[relikpL]

It would have been very helpful if you had mentioned that the Inside Global IP is actually the public IP of the router doing NAT

[mostafasaadinasab]

CCNP system admin Cisco systems and teaching scientists.

[thechronic]

somehow im more confused now than i was before..it could just be how gorgeous you are. your expression is excellent too. the cisco literature is pretty bland though. maybe some active drawings projected would be more attention grabbing and not so crammed in the one layout as well as not financially prohibitive. anyway i dig it. i subscribed :)