General Questions

does the net5501 run stable with the m0n0wall with captive portal working ?

It's reported the 5501 works fine with m0n0wall. Captive portal isn't specific to any particular hardware, I'm sure it'll work fine.

Depending on your needs, the 5501 might be overkill. The 4501 works fine too and can handle quite a lot of traffic.

I would strongly suggest against a 4501. They just aren't powerful enough going forward to use as a firewall. Newer OS's are slower than the older, now-dead releases. m0n0wall 1.3 will be based on FreeBSD 6.2, which is going to drop the max throughput of that device from around 17 Mb to 10-11 Mb or so (Linux is roughly the same). With increasing broadband speeds, that's not going to be fast enough for long in many areas. Captive portal deployments even more so since they route between wired and wireless networks frequently, requiring more throughput than you can even get with m0n0wall 1.2 and a 4501.

I had to retire my 4501 at home last year when my ISP bumped my cable modem to 15 Mb. Grab a popular BSD or Linux torrent, and it'd be pummeled to death with BitTorrent traffic at around 11-12 Mb with m0n0wall 1.2 even. Put in a faster firewall and I can hit 15 Mb every time with any popular torrent.

Until this weekend I was using a Geode 333 as my perimeter firewall:
http://ecommerce.herologic.com/oscommerce/catalog/product_info.php?products_id=62

swapped it to do some work with that device. With pfsense (FreeBSD 6.2), it handled dual WAN (15/1.5 Mb cable, 3/384 DSL) and could fill both the pipes simultaneously with some capacity to spare.

Point is, that's not a very fast proc and it worked great - the 4501 is just *that* slow.

that's a bad news btw that the newest version is slower ...
Pfsense was talking about that in their blog too, that they are strongly trying to have similar performance to the monowall on similar hardware.

Please dont forget that the first purpose is a firewall, not a wireless device.
If the firewall is getting a lot slower just to add some wireless features, then maybe you should make a fork of the project.

that's a bad news btw that the newest version is slower ...
Pfsense was talking about that in their blog too, that they are strongly trying to have similar performance to the monowall on similar hardware.

Yeah, I wrote 99% of that. 

Please dont forget that the first purpose is a firewall, not a wireless device.
If the firewall is getting a lot slower just to add some wireless features, then maybe you should make a fork of the project.

No, it's sacrificing some single processor performance to make significant gains with multi processor performance. With all common processors made in the last 1+ year having multiple cores, this is obviously the right thing to do going forward.

There isn't nearly enough manpower to maintain an entire old, unsupported OS release in addition to this project, and it's unnecessary. It's not just wireless that isn't well supported - numerous newer Ethernet NIC's, SATA, etc. that you find on new hardware either doesn't work or doesn't work well.

I understand better now.
Seems to be the right way to go indeed.
I'm just a bit affraid because all my monowall (and I have many) run on soekris 4501.
Of course i dont _need_ to upgrade, but i'm really looking forward to using that new group possibilities in alias and firewall rules (expected in the new beta ?)