Has anybody else had trouble trying to set up the DMZ for the PS3 on Cisco router
Try turning on UPnP for the PS3, but no issues with DMZ that I am aware of.
As Kevinds says, turning on UPNP is usually a better option, though some games do seem to have connectivity issues, particularly if you are running more than one PS3 unit in the house (we have 2... one for myself and one for my husband). At one point I did use DMZ on one of the PS3's to see if it was a port issue and I had no problems running one PS3 in DMZ but this is done through the router, so it really depends on the set up for your router. It should be a pretty simple option, though you have to assign the PS3 a static ID before putting it in DMZ.
The UPNP option being turned on with your router will resolve most issues, even though UPNP isn't showing on the PS3. I have UPNP enabled on my router, but my PS3 shows UPNP as being unavailable, so this may be a limitation with the PS3 because it does show as active on my Xbox. It usually works for most games though! (except for voice chat on Starhawk... which seems to be a port issue when two PS3's are online at the same time).
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