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    how do I get my "external IP address"?


    I am trying to find out my external IP address. Also I probably have a few misconceptions as to how ISPs and IP addresses work. First of all I connect to my ISP with DHCP. Currently when I check my IP address I see that my IP address is 10.200.18.159. This is a private IP address. These addresses are private and not accessible from the internet from my understanding:

    (10.*.*.*)
    (172.16.*.*) through (172.31.*.*)
    (192.168.*.*) through (192.168.255.255)

    So this means that my IP (10.200.18.159) is an address on my ISPs private lan.

    My major question is this: do I have an "public IP address" also? In other words; if I were to go to a different machine, outside of my home network, could I type in an IP address into a web browser and reach that machine (assuming I have a web server running)? I tried this one site that claimed it could tell me my address:

    http://checkip.dyndns.org:8245/

    and it returned:

    http://216.157.205.249/

    that dirrected me to a site that sells routers:

    www.MikroTik.com

    I guess the strange thing is that if I run a traceroute to any site I get this for the first few addresses:

    1) 10.200.18.1 (I am assuming a gateway or proxy of my ISP)
    2) 216.157.205.250 (the mikrotik website)
    3) 10.200.1.1 (I am assuming a gateway or proxy of my ISP)
    4) 63.89.180.254 (no idea)
    5) 64.186.46.5 (no idea)

    Is this maybe some technique that they use to mask my "external IP" address from me? Am I misled in believing that there is such a thing as an "external IP address"? I don't know all the inner workings of TCP/IP. But I am assuming that there is not a persistent connection. In other words; a client sends a request for a web page. The ISP does name resolution using a DNS server and forwards the request to the server that has the page. Does the web site then send out the page with the clients IP address (in which case the client would have to have an IP address that is accessible from the internet)? Or does the server simply return it to the ISP and the ISP handles getting it back to the client?
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    The way I find my IP is by opening a command box (Start > Run > "command" > enter)

    Then type ipconfig

    Hope that was what you wanted.
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    you can get your External IP Address using this website...

    just go to " whatismyip.com " to get your External IP, DNS server details, etc..

    ____________________________________
    "It will happen, when you take action."
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    As you've seen, your "internal" IP is different to your "external" IP.

    This happens because ISP's pool the IP addresses at a main router, and use that router to send out the requests for however many customers are connected to it. This means that the external IP address is the IP address of the ISP's router, and your internal IP address is the IP address of your machine that was assigned by the router so it knows where to send the data to so that it reaches your machine.

    At a guess I'd say that when you vist your external IP, you see a website that's not associated with anthing of yours because your ISP is using that IP address to host websites as well, and that just happens to be the "default" site for that IP address, so that's what's shown.

    In this scenario, you can't connect to your PC directly from outside your network, meaning that a normal computer can't connect to it through the internet.
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    You can get all the details about the IPs and name servers on Who.is and also can try on http://www.whatismyip.com
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    The easiest way in case you just want to know your public IP address is type in "my ip address" in Google and search. This will display your public IP address.
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    Hi,

    Before read your post, I am not aware about this process. I have find in Google for this process, and find it really great and depth information about that. You can also find here: lifehacker.com/5833108/how-to-find-your-local-and-external-ip-address
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    You can't get it directly from the machine you are on. You'll need to get a machine on the internet to tell you...
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    There were many tools available online to find out the IP address.
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    good grief people...this thread is from 2004.
    If the OP hasn't found out how to get their external IP by now, there is no hope for them.
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    I am now subscribed to this thread. Anyone who posts any of the following will be considered a spammer and banned:
    * A repeat of anything already mentioned in the thread
    * A reply saying how someone else's recommendation is good or helpful
    * A recommendation for any other websites used to determine your external IP
    * A short post that adds nothing to the thread


    Spammers zapped to date: 2
    Last edited by Kravvitz; January 20th, 2014 at 03:29 AM.
    PHP FAQ

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    Ah USB, the only rectangular connector where you have to make 3 attempts before you get it the right way around
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    Internal and External IP Addresses


    Originally Posted by Catacaustic
    This means that the external IP address is the IP address of the ISP's router, and your internal IP address is the IP address of your machine that was assigned by the router so it knows where to send the data to so that it reaches your machine
    There's been a lot of misinformation in this forum about internal and external IP addresses.

    Everyone has a Local Area Network (LAN) at home these days, but you could have just a single host like we used to. If you did, then your host would obtain an IP address from your ISP via Dynamic Host Configuration Protocol (DHCP). DHCP is not how you access your ISP, as one poster said; it's just how you obtain an IP address and other configuration parameters from your ISP. The address that you obtain is sometimes called your external address, but is properly called your global address. This is because nobody else on the planet has the same global address as you. Your global (external) address is NOT the address of the ISP's router, as one poster said. It is YOUR address.

    Now, if you have multiple network nodes (hosts, printers) at home, then you need a LAN. The LAN is built around a switch. Usually you don't buy a separate switch; you use one that's built into a residential "router", which includes your wireless access point too if it's a "wireless router." So your wireless router is really three components in one: a wireless access point, a switch, and a router. Routers connect networks. Your router (just the router part of your "router") connects the ISPs network to your LAN (which is a network). Since your router has one foot in the ISPs network, it needs to obtain a global address from the ISP via DHCP. So when you have a router and a LAN at home, your global address is the IP address of the router's Internet interface. Your router has a separate address for its LAN interface; this is the address that you see in ipconfig as your Default Gateway.

    If you have a residential account with your ISP, then you only get one global address. If you have a business account, you might get multiple global addresses. Let's stick to a residential account. If you only have one global address, then to the outside world your LAN appears to be a single host. So how do messages from the Internet get to the correct host on your LAN? The answer is that every host on your LAN has a unique local address, but these addresses are not visible to the outside world, which sees only your single global address. A supplementary function of your router is Network Address Translation (NAT). NAT keeps track of connections that your hosts establish to hosts out in the Internet, and translates your local IP address and port number (port numbers are for another day), to the global address and possibly a new port number. When the reply comes back from the Internet host to your global address and new port number, the NAT translates that back to your local address and old port number. Your host has no idea that this is happening. That's why when you ask your host what its IP address is using ipconfig (Windows) or ifconfig (Mac, Linux, UNIX) it only knows to reply with its local address.

    Your hosts only know their local addresses, but every host on the Internet can see in your return address (called the source address of your outgoing packets) what your global address is. So the easiest way to determine your global address is to ask any Internet host. This is usually done with ipchicken.com or whatismyip.com. Those sites will create a web page with text containing your global address and send it back to your global address in the destination address field of the packets carrying that page. Your NAT will translate that global address to your local address so that your host can be found on your LAN, but the text of the page will be unaltered.

    I hope that isn't too long-winded.
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    Welcome to DevShed Forums, RBandes.

    Out of curiosity, how much have you studied networking? Are you certified as CompTIA Network+ or any level of Cisco certification?

    Everyone has a Local Area Network (LAN) at home these days, but you could have just a single host like we used to.
    Do you mean you consider it to be a LAN even if a router is not used so the one computer is directly connected to the cable/DSL "modem"?

    I find some of the reviews on NewEgg and Amazon amusing when people don't understand the difference between switches and routers and so purchase the wrong device, expecting it to do what they want, and then get upset when it doesn't.
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    Originally Posted by Kravvitz
    Welcome to DevShed Forums, RBandes.

    Out of curiosity, how much have you studied networking? Are you certified as CompTIA Network+ or any level of Cisco certification?

    Do you mean you consider it to be a LAN even if a router is not used so the one computer is directly connected to the cable/DSL "modem"?
    Thanks for the welcome. I have been involved with networking since 1977. I do have a Network+ and used to teach it at The Chubb Institute in NYC. I was a CCNP, but allowed that to lapse 5 years ago.

    I would not consider a single host to be a LAN. Your bringing up the matter of a router being present is exactly the crux of the matter. A router connects networks. You will always find a router between networks, although it might be called something else like a firewall. Two hosts communicating without routers must be on the same network.

    HTH,
    Ron
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    Wow. Ok. So you definitely have a great deal of experience in this, probably more than the professor who instructed me.

    Thanks for clarifying that.

    If you don't mind, I have a hypothetical question to which you are likely to know the answer. Is it possible to have a setup with some hosts having some addresses with different subnet masks on the same network without requiring a router to connect them? Must a host's subnet mask match that of the router/gateway it connects to?

    Also, I'm curious, how did you stumble across this thread anyway? It seems somewhat unlikely you would do a search for a question to which you know the answer so well.

    Hopefully this bunny trail won't scare the newbies too much...
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