uhh Ace...thats not what DMZ is about, it deals with the router, and opening ONLY the connection with the psp without any security to cause problems...nothing to do with flash, but DO NOT do this to a PC as it will open up your computer to be very vunerable to malicious attacks.
1. Setup your console with an static IP address (do not let it be set to automatic) that does not conflict with others on your network.
2. Then access your settings, find “DMZ”, or De-Militarized Zone. It is a place that is UNPROTECTED by any firewall/router from an attack.
3. Once you input the IP you set for the console into the DMZ, save your settings and reboot both your router and the console.
4. Once connected, the next time you play the game of your choosing – you will not get any warnings and see much better connections with friends and others when communicating.
NOTE: This is fine with consoles, but not with your PC. A computer on the DMZ is susceptible to any hack attempt and will rely on firewall and anti-virus to protect you. It is generally unwise to use this method for a computer.