Is it possible to obtain the IP address from a HTTP Request
Question: **I am trying to identify users that access my website. I know of assigning a
cookie to them & identifying them that way. But is it also possible to use
their IP address to identify them?**

I know of IP subclassing (is that the correct term) so if many users on the
same network access my site & have subclassing, they will all have the same IP
address but thats ok, I dont want my IP identification to be exact, its just a
backup if the user has no cookie.

If I have a HTTP request can I get the ip address of the requester/sender? For
example to get the browser type I check the HTTP (header?) user-agent. With my
little knowledge of Data Communications, if the HTTP request does contain an
IP address, wont it have the IP address of the last hop(router/switch) or am I
thinking of TCP?

**I am using Python & cgi; so is there a way to determine the HTTP requesters
IP address either by looking at the HTTP request, or maybe TCP packets(I never
worked with TCP in python, how could I look at data packets in python?).**


Answer: Sure. Use `cgi`, and `os`. The client's IP address is located in the `environ`
variable with a title of `REMOTE_ADDR`. For example, the following will print
out the client's ip address:

    
    
    import cgi
    import os
    
    print "Content-type: text/html"
    print ""
    print cgi.escape(os.environ["REMOTE_ADDR"])
    

