visitor (0 QPoints)
  • FR
  • EN
  • NL
  • DE
  • ES
315 experts, 1193 registered users, 1659 questions already answered
European Experts Exchange, the very best site for high-quality IT solutions

New Improved Search!

 


05/10/2011 1h30 : Steve Jobs is dead, the father of Apple ][ is gone, we are all orphaned.

Languages :: Delphi :: Bypassing the firewall
By: collegeBoy U.S.A.  Date: 02/11/2002 00:00:00  English  Points: 75 Status: Answered
Quality : Excellent
Hi.

Me and my friends are setting up an online programming contest . We have finished writing both the server and client apllication in delhpi but the problem is that we are using one the school's computers as our server and when the clinet program tries to connect to the server from a computer outside the school's network, school's firewall doesn't allow the client to connect to the server. Is there anyway for the client program to bypass the firewall inorder to connect to the server ?
By: VGR Date: 02/11/2002 10:41:00 English  Type : Answer
No. I guess you have thos eproblems because you used a "special" port, which is closed by the firewall.

personally, I always use port 80 as it is usually open ; of course this means I can install specific PHP scripts or CGI binaries on the web server, but you should also be able to 8-))

Bypassing is impossible, unless you obtain from the FW maintainer people that your remote client be a "trusted host", or that they open your special port for its @IP (if fixed). Those are only example of possible solutions 8-)

good luck
By: Squibi Date: 02/11/2002 16:06:00 English  Type : Comment
you may also use Socks 4,5 connection if it is available
By: TheFalklands Date: 04/11/2002 20:37:00 English  Type : Comment
Generally firewalls will be configured to only allow data in on port 80 if the request orginated from within the firewall. I would doubt very much that you would be able to host a server inside on port 80.

In addition, the network within the firewall has it's own private IP range e.g. 10.100.x.x or 192.168.0.x. The firewall however only has one ip address which is accesible from the internet. Therefore, without any firewall configuration, there is no way of accessign a internal server from the outside via the firewalls ip address.

The only way to do this, is to set up a single port on the firewall to forward all data on this port to a single internal server. This is called Port Forwarding and must be setup by the administrator of the firewall.

To summarise, if you could bypass a firewall what would be the point of having it ?

Do register to be able to answer

©2010 These pages are served without commercial sponsorship. (No popup ads, etc...). Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE.
Please DO link to this page! Post to Twitter Post to Plurk Post to Yahoo Buzz Post to Delicious Post to Digg Post to Facebook Post to MySpace Post to Ping.fm Post to Reddit Post to StumbleUpon

EContact
browser fav
page generated in 294.353960 milliseconds

Why Google AdSense ads ?
compteur
 Ranking-Hits PageRank for this page