When I got the details from the ISP it labelled the .208 address as the router's address, so I never used it, if I can use it the same way as .209 though .214 then great.
Since there has been one show stopper though. When the modem sends the public IP to the router it adds a few entries to it's own routing table
Code:
123.123.123.209 * 255.255.255.255 UH 0 0 0 br0
default * 0.0.0.0 U 0 0 0 ppp0
In the new configuration everything as static on the router, and the modem never adds these entries. I can save an xml file of the devices configuration, and using another entry as an example (for the Multicast block) I've added the entries for all my public IPs, then restored the devices config with the edited XML file. However I've been unable to figure out how to add the default route for ppp0. This is really another problem - it doesn't help matters that the squashfs 1.0 isn't supported by modern versions.
The old combined router/modem handled this no problem, but it didn't support modern ADSL speeds and I had no say in the new modem or router. The new router died and I managed to get a FreeBSD PC in to do the routing.
Anyway, any tips on the Dlink 300T would be welcome
Thanks again, J65nko
Oh, the other thing is the modem every so often loses the connection and renegotiates, and as part of this process it's routing table is reset, so manually adding the routes isn't an option, it has to be fully automated, I lost connectivity to my network yesterday when I was at work.
I think the plan of attack is to install Slackware from circa 2004 along with squashfs-tools from the same period, in a VM, mount the squashfs filesystem, edit an init script, re-squashfs the filesystem and watch myself render the modem useless.