I’ve currently own a Linksys E4200 and a Thomson 546v6.
Because I have an IPTV service I must set the Thomson as the main router connected to the phone line so that I can distribute the video signal for 2 specific ports and the other two for LAN Access.
The problem is that the Thomson doesn’t like port forwards, it usually doesnt work and since I have a good router (linksys) currently only working as Access Point I would like to use it as a router itself.
I don’t want to do a NAT beyond NAT so my question is should I connect the E4200 and to thomson and set the E4200 as a DMZ machine and then control all trafic on the E4200 itself or is there any other option that could suit my needs better?
In theory, that should work, at least as far as I can tell. However, I seem to recall that at least one program will refuse to run in a DMZ, but be fine on a direct connection (the program in question is Steam as of the last time I really used it, which was several years ago when Windows was my primary OS, so YMMV). I suspect that any such program would have similar problems in the setup you describe.
Another option, more involved but arguably more elegant, would be to set the Thomson (which, incidentally, is really a rebranded Speedtouch) up in bridge mode, rather than putting the E4200 in the DMZ. I don’t know if that would allow the IPTV to continue working, however, so you’d want to look into that There’s some information on doing this (you have to use the telnet config interface for the Thomson rather than the browser-based one) at http://www.roysindre.no/a/2010/11/30/speedtouch-bridge/