Re: Natted IP

From: Stuart M (dfdgh_at_fghf.cvgd)
Date: 02/18/05

  • Next message: Stuart M: "Re: Natted IP" 
    Date: Fri, 18 Feb 2005 17:40:37 -0000

    "Bill Unruh" <unruh@string.physics.ubc.ca> wrote in message
    news:cv3acs$277$1@nntp.itservices.ubc.ca...
    > "Stuart M" <dfdgh@fghf.cvgd> writes:
    >
    >
    >>"Steven Wayne" <swayne@power.net.uk> wrote in message
    >>news:slrnd19icp.5eu.swayne@wayne.power.net.uk...
    >>> On Thu, 17 Feb 2005 16:08:21 -0000, Stuart M
    >>> <dfdgh@fghf.cvgd> wrote:
    >>I thought the browser sent a request to the router asking for a webpage,
    >
    > The browser sends out a packet with a to and from address and port. The
    > router with NAT, replaces the from address and port with its own address
    > and some high port number-- having assigned your machine some range of
    > port
    > numbers.
    >>telling the router to send the data back to 192.168.1.10. The router then
    >>contacts the website and asks for the data, telling the site to send data
    >>back to my external ip . The router then routes the traffic back to the
    >
    > That packet, whatever its contents is sent to the far site. That site
    > responds to the From: address in the packet. When your router receives
    > that
    > packet it looks at the port, realises it is for your machine, and
    > translates the To address and port for your machine, and sends it to you.
    >
    >>browser on 192.168.1.10. I thought that the router hides the internal ip
    >>from the WAN.
    >
    > It does.
    >
    >>I dont see why the browser would send out the internal ip to the WAN
    >>anyway.
    >
    > It doesn't. The return packet from the far system is an http packet which
    > tells your browser "Display the following text" "Display the IP address of
    > the machine this sentence is being interpreted on" That is your machine.
    > It
    > is your machine displaying its own IP address. The remote system did not
    > send your IP, it sent a command to your machine to display its own
    > address.
    > That is why shutting off activeX or javascript will mean your own machine
    > cannot run commands like "display IP address"

    Hi Bill,

    thanks for that, I found it very interesting.

  • Next message: Stuart M: "Re: Natted IP"

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