said by morbo:Netgear 6200 is what I have.
If you have an AT&T branded 6200, then I think you are not going to be able to change the LAN IP subnet. If I am mistaken about the AT&T version capabilities, I suspect that someone who is familiar with that particular box will probably correct my statement. If you are wanting to change the LAN IP subnet because you plan to connect it to another (better) router, you may want to consider putting the 6200 into bridge mode and doing the PPPoE authentication on the other router. Here is an old DSLR thread about putting the 6200 into bridge mode: »
[Modem] Westell 6200 modem (its private LAN IP address will still be 192.168.1.254, but the PPPoE client in the other router will not use an IP address to access the 6200).
If you have a generic Netgear 6200, you can download the user manual from »
www.downloads.netgear.co ··· ct08.pdf and the information you want is in the LAN IP Setup section.