On 12 Oct 2006 13:41:17 -0700,
(E-Mail Removed) wrote in
<(E-Mail Removed) .com>:
>1) For most people, their connection is to a defined IP range owned by
>a single ISP provider, who probably gives its users the modem to use,
>and thus, these modems are all probably of a certain make, and all have
>the same first 3 hexadecimal numbers.
Most non-trivial providers wind up supplying different hardware, sooner
or later, so there's usually a mix of products in the field. In
addition, some users may buy their hardware from a third-party source.
>Thus, since all users in that IP
>range would share identical hex values in the first 3 digits of their
>MAC address, if you randomized your entire MAC address, you would stand
>out as the user with a different beginning MAC address than the rest.
>It would be better, for the sake of anonimity, to keep the original
>first 3 numbers and randomize only the last 3. Am I correct?
Why would you want to change your MAC address? You're identifiable by
your IP address.
>2) Using a sniffer, I can see that random packages sent to my IP
>address by all those bots and whatever that are out there, already know
>my MAC address without any communication from my part. This happens
>even when I start my internet connection and I have been online for
>only half a second, the first random bit of internet noise that hits me
>already knows my MAC address despite my not communicating with anyone
>besides my ISP to establish the connection. How does this work? Is my
>modem changing the MAC on incoming packets? Or my ISP?
Those things out there just use your IP address. Your MAC address comes
from ARP. (Look it up in Wikipedia.)
>3) If I open my ISP monitoring window it shows me sent/received bytes
>to the internet. By carefully following this flow with the sniffer, I
>realized that there is a discrepancy, and that almost every packet
>sent/received, according to the sniffer, is 20 bytes longer than
>according to the ISP window. Any reason why (and which) 20 bytes would
>be underreported from every packet (almost every packet)? The ECHO
>packet behaves differently: my ISP window shows a flow of about 20
>bytes per packet, while the sniffer program reports 50 to 60 bytes
>(don't remember the exact number).
Read up on Ethernet. (Wikipedia again, as a starting place.)
>4) Is there a website that will show you a print out of the packet you
>send it, the same way there are web sites that show you the details of
>your web request (such as IP address, what IE you're using, etc.)?
You wouldn't learn anything more than by sniffing yourself.
--
Best regards, FAQ for Wireless Internet: <http://Wireless.wikia.com>
John Navas FAQ for Wi-Fi: <http://wireless.wikia.com/wiki/Wi-Fi>
Wi-Fi How To: <http://wireless.wikia.com/wiki/Wi-Fi_HowTo>
Fixes to Wi-Fi Problems: <http://wireless.wikia.com/wiki/Wi-Fi_Fixes>