tcp/routing question...

[Andy Green]

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bruce wrote:

| question.. is there a way for me, as the person running a server, able to
| determine the actual ip address of the client that i'm talking to. or
is it
| seriously easy for a client (man in the middle) to spoof the ip
address. in
| which case you can never be completely sure as to who you're talking to...

It's not generally possible to really spoof your IP address on a TCP/IP
connection, where that means you appear to be coming from
123.123.123.123 when you are at 4.4.4.4, and you have no contact or
control over 123.123.123.123.  (Google "three way handshake" for the
reason why).

What is certainly possible (even easy) is to proxy through another
machine... in the case above if you did control 123.123.123.123, the guy
at 4.4.4.4 could proxy through it and appear in your logs as being at
123.123.123.123.

- -Andy
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