Actually, there are many cases where the router changes the FROM address -- Network Address Translation (NAT) does just this. Those home ADSL networks with many computers often do this kind of translation (it's reversed when the packet comes back). It's also not uncommon for remote offices to have this kind of translation as well.
It's best these days to assume that the IP address you see has nothing to do with the user when dealing with the public Internet. Proxy Servers, NAT and any number of other things mess with this. Clayton -----Original Message----- From: A mailing list about Java Server Pages specification and reference [mailto:JSP-INTEREST@;JAVA.SUN.COM] On Behalf Of John Ghidiu Sent: 17 October 2002 19:19 To: [EMAIL PROTECTED] Subject: Re: about getRemoteHost() In fact, if the router does change the FROM field, the TCP/IP connection is effectively terminated because the receiving end can no longer reply (even with an ACK) that the packet was received. However, a proxy is allowed to (and often does) change the packet. Be aware of that in your programming (which means, among other things, no session tracking via IP address). John -----Original Message----- From: Peter Dolukhanov [mailto:peter.dolukhanov@;NCL.AC.UK] Sent: Wednesday, October 16, 2002 10:17 AM To: [EMAIL PROTECTED] Subject: Re: [JSP-INTEREST] about getRemoteHost() >From my knowledge of networking, a router (or routers) will not change the >From field of an IP packet, they just forward the packet onto a node closer to it's destination. As even this e-mail bounces through umpteen routers, and none of these will modify the remote address. So, as far I can tell this won't happen - what you have to worry about is Web Proxies as these do send the request to the web server themselves, and your web server will see them as the remote host and not you. Regards, Peter Dolukhanov -----Original Message----- From: A mailing list about Java Server Pages specification and reference [mailto:JSP-INTEREST@;JAVA.SUN.COM] On Behalf Of randie ursal Sent: 16 October 2002 03:07 To: [EMAIL PROTECTED] Subject: about getRemoteHost() hi, i want some idea on this. i have a setup where my WebServer is separated by a Router from a User. when the user access the webserver it has to pass through the router, so my question is what would be return by the method getRemoteHost()? is it the IP address of the Router or the User Workstation? thanks a lot. randie ======================================================================== === To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com =========================================================================== To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com ========================= To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com ==========================================================================To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST". For digest: mailto [EMAIL PROTECTED] with body: "set JSP-INTEREST DIGEST". Some relevant FAQs on JSP/Servlets can be found at: http://archives.java.sun.com/jsp-interest.html http://java.sun.com/products/jsp/faq.html http://www.esperanto.org.nz/jsp/jspfaq.jsp http://www.jguru.com/faq/index.jsp http://www.jspinsider.com
