Questions about IP

Discussion in 'Mac Basics and Help' started by doubledee, Dec 14, 2014.

  1. doubledee macrumors 6502

    doubledee

    Joined:
    May 14, 2012
    Location:
    Arizona
    #1
    My friend and I are debating about IP addresses, and maybe you guys here can help settle the debate...

    In the old days, when all Internet access was done through a *wired* dial-up, cable, or DSL connection, it is my understanding that websites would identify your Macintosh via its IP address.

    But in the *wireless* age, I don't think it works the same way.

    For instance, if I was making this post from McDonald's free wi-fi, wouldn't MacRumors see McDonald's free wifi hotspot's IP address instead?

    Or if my was connecting to www.cnn.com via his Verizon hotspot, wouldn't CNN see his Verizon hotspot's IP address as who was connecting to the site?

    Sincerely,


    Debbie
     
  2. Alrescha macrumors 68020

    Joined:
    Jan 1, 2008
    #2
    Correct.

    Also correct.

    The only addition I would make is that this is not a wired vs wireless issue, if you had plugged your laptop into your friends router, then CNN would see his IP address.

    A.
     
  3. doubledee thread starter macrumors 6502

    doubledee

    Joined:
    May 14, 2012
    Location:
    Arizona
    #3
    Okay.


    Okay.


    Okay, thanks.

    But what about the end computer connecting?

    If I plugged my MacBook Pro into my friend's wired (or wireless) router at his place, and then I went to www.ccn.com, wouldn't CNN also be able to see my Mac's IP in addition to my friend's router's IP?

    Sincerely,


    Debbie
     
  4. Butchie-T, Dec 14, 2014
    Last edited: Dec 14, 2014

    Butchie-T macrumors regular

    Joined:
    Oct 29, 2014
    Location:
    Colorado
    #4
    Because it is a pretty good bet your IP address will be within the private IP space of your friends router, CNN would not see that private IP address. CNN would only see the routers public facing IP address that was given to it by the ISP.

    RFC 1918 describes the private address space. Your friends router is performing a NAT function on that private IP address to get to the Internet. Hence, the address that CNN would see would be a public one.
     
  5. hallux macrumors 68020

    hallux

    Joined:
    Apr 25, 2012
    #5
    This is something called NAT or Network Address Translation. The router has a "public" IP, ALL traffic from the "private" side of the router going to the internet will show as coming from the "public" IP. The router has logic to know what requests came from what computer/device, as the responses to those requests come back the router identifies where to send it and your computer gets the data you requested.

    Pretty much any network connection where you have many devices connecting through a single ISP connection works in a manner like this.

    https://en.wikipedia.org/wiki/Network_address_translation
     
  6. hiddenmarkov macrumors 6502a

    Joined:
    Mar 12, 2014
    Location:
    Japan
    #6

    This one of many things that will affect what the world sees.


    You can throw even more layers on top. Example would be me. I am an US expat of sorts in Japan. I use a lot of US based resources.

    My problem: for some things some US entities do not like incoming address from outside the US. So....I pay for a vpn service. I connect to their VPN servers which then give the abilty to have me broadcast as having an IP address from the block of IP's assigned to the US (long story short every country is giving a block of ips from an internet governing body).

    You don't have to be overseas to use this, some use this for internet anonymity even in the US (or country they call home and vpn services offered there).
     

Share This Page