I had previously setup this site using a Watchguard Edge X10 firewall with a Cisco SB107 router in pure bridging (RFC1483). On the Watchguard I had then entered the details for the PPPoE authentication, and everything has been working fine.
At the time, they were using an ISP that supported both PPPoA and PPPoE.
Now they have changed ISP and the new one uses only PPPoA (with CHAP authentication).
How can I approach the problem? I have heard of half-bridging, this method should let my ISP assign the IP to my router which would have DHCP server active. The IP would then be spoofed onto the Watchguard firewall, which would have the WAN interface set in DHCP client mode. And my LAN would be set with LAN addresses (192.xxx.xxx.xxx). This should work isn't it?
However, this ISP gives 8 static IPs. Actually we are not interested in those IPs, having only one would be fine if this is the only way I can approach the problem. Instead if I wanted to use also those IP addresses what should I do??
Please help me, this is quite urgent as they are experiencing problems with the other ISP and need to switch as soon as possible!