SitePoint Sponsor

User Tag List

Results 1 to 4 of 4
  1. #1
    AdSpeed.com Son Nguyen's Avatar
    Join Date
    Aug 2000
    Location
    Silicon Valley
    Posts
    2,241
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I use php to get the IP:
    $ip = getenv("REMOTE_ADDR");

    Could there be a case when $ip is undefined?

    Thanks
    - Son Nguyen
    AdSpeed.com - Ad Serving and Ad Management Made Easy

  2. #2
    Destiny Manager Plebius's Avatar
    Join Date
    Nov 1999
    Posts
    682
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I don't think so. Unless maybe you're invoking the script from the shell.

  3. #3
    SitePoint Wizard
    Join Date
    Apr 2000
    Posts
    1,483
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I think there are programs that act as proxy servers that go between the browser and net connection which fiddle with the headers. I know there are ways to change your USER-AGENT so that it looks like you are using Linux or something. But I don't know if the same thing can be done with the IP addresses.

  4. #4
    SitePoint Evangelist
    Join Date
    Jul 2000
    Location
    Warwickshire, England
    Posts
    557
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    What you're thinking of is blind IP spoofing.
    I wrote one a while ago with UDP datagrams etc, but the problem is if some one sends you data with a forged IP address, the data must be a)under 512 bytes (there is no way for the server to send back the SEQ number) and b)Data cannot be recieved by the person making the request.
    This is mainly why people use it to send small emails etc. But under most circumstances, there would be an IP address.


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •