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[_] ADSL modem & multiple WAN IPs

Oliver Humpage oliver at watershed.co.uk
Wed May 30 22:02:14 BST 2007

We've got an ADSL backup line, and I've just got a small block of IPs from
Plusnet (who really did have excellent customer service). What I want is to
create a network where I can plug in a piece of kit, give it one of these
public, routable IPs, and it's on the internet. I currently have a Dlink
DSL-300T.

However, although this is possible with most ADSL modems for a *single* IP
(i.e. just switch off the NAT), it seems that multiple IP addresses present
a problem - the modem only thinks it's getting one WAN address, and that's
all it's prepared to handle. I could just put the modem into "bridge" mode,
but then any connected device has to use PPPoE to authenticate, which isn't
fun. Is my understanding of that correct?

I also don't want to use NAT at all, not even "static" nat (at least, not
visibly) - for various reasons, not least of which is I like servers having
the IP address they have in the real world.

So, anyone know of any hardware which will pass-through multiple routable
IPs from an ADSL line, without me building a *nix box with an ADSL card in
it (or putting two routers back-to-back and double-natting)?

Thanks,

Oliver.