Some very good alternatives to running PPPoE on your hardware device or DSL/iBurst client:
pfSense:
In my opinion the best firewall. The latest release is 1.2-BETA-2 and commercial support is available but not needed as they have excellent support via mail distribution list or forum. Tested and working with 2 different PPPoE dial ups on 2 routers with CARP, DHCP failover, WAN outbound AND inbound load balancing and fail-over. It has a package loading and versioning system. Extra packages and inbuilt features include: Squid transparent proxy, Captive Portal, Radius, VPN, SIP, Traffic Shaper and ntop. As simple to setup as any of the others but very feature rich. Has WLAN support via PCI Card Carriers(AP Mode)! And it will run on a WRAP using a minimum of 8MB flashcard and 64MB RAM memory.
http://www.pfsense.com
m0n0wall:
m0n0wallm is a simple and effective firewall on which pfSense has been based.. It will run on just about anything. It has a captive portal with MAC filters and most of the other nice features of pfSense.
http://www.m0n0.ch/wall
FreeBSD:
FreeBSD is the daddy from which pfSense and m0n0wall orginate. One of the most powerful Unix operating systems available today. It's also 100% free and used in many different instances where a reliable, secure, and stable operating systems is needed. Just to give you a idea, it is used in Mac computers, checkpoint firewalls, it was used in a clustered environment for the raw number crunching of the movie the matrix and many different ISP's make use of it including IS ,MWEB Business and UUnet.
The minimum specs are a couple of gigs hdd, 128MB memory and thing from a P1 and upwards for the cpu.
A bit of learning is needed but most of what you need can be found here: http://www.freebsd.org and there is also a free book which you can go download here http://www.lemis.com/grog/Documentation/CFBSD/
Mikrotik
There are several pfSense systems currently running on the network, but even more users are opting for Mikrotik RouterOS (http://www.mikrotik.com) due to its powerful firewall system, not to mention the fantastic Wireless capabilities.
JAWUG