Broadband Static IP allocation

[JerryBarrett]

Hi Guys
I have a system which uses dual ADSL lines for bandwidth management and load sharing as well as redundancy.

Each ADSL line has an ADSL modem or modem/router connected via a short ethernet cable to the firewall ports.

I have a block of IP adresses allocated by the ISP - what do I do with then and how do I config the modems or modem routers.

Previously on static ip designation I have bridged the modem and the router takes on the IP of the frame relay to the ADSL modem, but this seems not to be the case with fixed IP blocks.

My thoughts on this are:

|
V
Frame relay ip (194.164.86.99) for example
|
V
Modem (in PPPoA mode) NO-NAT?
(Dlink DSL 300T adsl eth modem)
|
Modem management IP (internal eth) 194.164.174.20
(first IP in block of IP's provided)
netmask 255.255.255.252
|
|
V
Firewall/Router/VPN (external eth) 194.164.174.21
(second IP in block of IP's provided)
netmask 255.255.255.252
|
NAT
|
V
General LAN (192.168.0.0) 255.255.255.0
|
V
Firewall/Router/VPN (internal eth) 192.168.0.x)
|
|
V
DHCP Clients

What do you think? I seem to be having recurring problems with getting these modems to work (surf the web, they connect to the broadband fine), I think its because they are in NAT mode, I don't think I get get them to do NO-NAT with PPPoA, only in bridge mode using PPPoE on the Firewall/Router. How does that work?

Your thoughts or experience with this would be appreciated

Or any reference for dummies would be cool

Many Thanks
Jerry