Hej Niels, jeg fandt nedenstående som tyder på du ikke har ret.
Jeg har kikket i en TCP og en UDP pakke og der er faktisk informationer om
Destinations MAC og Source MAC, så den pakke en given maskine modtager fra
mig må kunne se min MAC adresse.
Jeg kan dog se at min maskine sender til min router, så pakken der udgår fra
min router har routerens MAC mod min ISP, så deraf kan jeg god se lidt af
det du er inde på. Hver gang der routes skifter pakken MAC adresse efter som
hvor den kommer fra, er det ikke rigtigt antaget.??
Det kan være at der findes en server der planter et lille program på ens
maskine og derved får informationer om ens MAC adresse.
Hilsen
NIC.
First of all, we concluded that TCP/IP hands in your IP address, and this
address can be used to find out who your ISP is, and possibly track your
geographical location.
Now you must be asking yourself "why does TCP/IP give this information if
people can use it to find all of this information about me?". Well, the
answer is quite simple. TCP/IP has to put your IP address in the IP header
of the packets that you send, because otherwise, how would the server that
you are requesting the web page from know where to send it back? If your
packets won't contain your IP address or will contain a fake address
instead, you won't receive the returning packets.
However, there's a workaround for this. What if you could tell some sort of
a public computer to retrieve the files for you, and then have the public
computer send the files to you? That way, the IP address that will appear in
the packets will be the address of the public computer, and your IP will
remain anonymous, right? This is called bouncing, because you send the
packet to the public computer, and then the public computer sends the packet
to the web server, so your packet metaphorically "bounces" from one computer
to another in order to hide your true address. I will explain how to bounce
a connection to a web site in a few minutes.
The other problem with TCP/IP is that it gives away your MAC address too.
Oh, wait, I haven't explained what a MAC address is!
Info Break: What is a MAC address?
A MAC (Media Access Control) address (also called an Ethernet address or an
IEEE MAC address) is a 48-bit number (typically written as twelve
hexadecimal digits, 0 through 9 and A through F, or as six hexadecimal
numbers separated by periods or colons, i.e. 0080002012ef, 0:80:0:2:20:ef)
which uniquely identifes a computer that has an Ethernet interface. Unlike
the IP number, it includes no indication of where your computer is located.
To learn more about MAC addresses, head to WhatIs.Com's definition of a MAC
address at
http://whatis.techtarget.com/WhatIs_Definition_Page/0,4152,212506,00.html.
Now, why a dial-up Internet user would have a MAC address is really beyond
the scope of this tutorial, but the point is that you have such a thing, and
since it's a 48-bit number, there are billions of different combinations and
your MAC address can be used to identify you (not in a very reliable way,
but it has a good enough success percentage). This form of identification
can be used to track your online shopping habits, for example (it is known
that some online retailers pass this kind of information from one another).
So in other words, exposing your MAC address isn't too good either.
So, the second privacy risk we talked about was your browser giving all this
information about your computer, right? And of course, your cookies file is
being exposed to the entire world. Wait, I haven't even explained what
cookies are yet!
">
> Det virker gennem hubs og swithe men ikke gennem routere. Så hvis der var
et
> site på internettet som viste Mac adressen, så skulle sitet sidde inden
din
> ISPs router for at du ville få noget ud af det.
>
> Niels Dybdahl
>
>
>