Internal/External IP

I was just wondering, what's the difference between an internal and external IP? I came over this when I got a different external IP by my ISP about a month ago. Until then, i had only one I think.

Thanks

sorry, i don't understand your question.

Computer usually only have one IP.

Router who do NAT job have two IP. One IP External (Internet), One IP Internal (Internal Network)

Do you have a router? Or you are plug directly into the modem of your ISP?

typically every MAC address (the hardware address of the network card) is assigned 1 IP address (either by a dhcp server or statically assigned)

the difference between internal vs external is that for the most part an internal ip address is private and cannot be accessed from the outside world. the external IP address is typically assigned by your ISP and is accessable by all.

if you have your router/firewall setup correctly there is no way for communication not started by you to get into your internal network. the way this is done is through something called NATing which means Network Address Translation. NATing works by you starting the communication with the external server. your router works as a middle man where it changes the port (ex website on port 80) to a higher (ephemeral) port and then any communication that comes from the server that you started communication with goes to that port and then the router will forward that information to your computer.

i hope this helps

I'm directly plugged in to the modem, I don't have a router.

First sign of the change was when ZoneAlarm configured a new IP address. I thought the ISP just changed the IP. When i visited a computer site, they said that they don't allow proxies. My proxy servers weren't on, and the site showed me my old IP as an internal one, and the new one of an external. I checked in IE, and no proxy servers are configured.

internal = inside

external = outside

Now if you're asking the difference between a public address and a private address that's different.

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NeonWizard,
I assume you are using Windows? Type ipconfig (WinNT, XP, 200) or Winipcfg at the command line at tell us what IP it says you have. It’s possible that your modem also has a built in router (I’ve ran into DSL setups like that before).

Not to go off-topic but :

Quote:

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It's time to put an end to malicious code & black hat hackers - Use a firewall and anti virus!

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Not alway's true. Anyway's, Korp and SDK summed it up pretty good. However it could be a different scenario if you're behind a router or are configured into a network. Single user PC's are different.

To expand on what they said in short:

Internal/LAN IP: IP your LAN sees (if you're on one). Example: 192.168.1.20
External/WAN IP: IP the rest of the world sees (given you by your ISP). Example: 64.66.120.7

I was confused on this recently too, and now I have it drilled in my head. :D

but how can i connect to a PC or Whatever a Machine thats Behind.. NAT !!
Mix the Two Ips :D !!

Yeah you add them together, mix them up. Since you dragged this old thread out this is how you do it. You add one IP to the other and connect to the resultant IP. Here's how...

12.34.124.101 First IP
12.666.3.23 Second Pagan IP
-------------------
24.700.127.124

That instantly bypasses ALL security because the host computer gets an I.D. 10 Error with a tee factor.
:rolleyes: