I can't find information is there linux or BSD distribution with effective firewall that uses optimized algorithm to store hundreds of IPs and to forward huge traffic. Any idea?
Hundreds?
http://www.openbsd.org/faq/pf/tables.html
"A table is used to hold a group of IPv4 and/or IPv6 addresses. Lookups against a table are very fast and consume less memory and processor time than lists. For this reason, a table is ideal for holding a large group of addresses as the lookup time on a table holding 50,000 addresses is only slightly more than for one holding 50 addresses. Tables can be used in the following ways:
* source and/or destination address in filter, NAT, and redirection rules. * translation address in NAT rules. * redirection address in redirection rules. * destination address in route-to, reply-to, and dup-to filter ruleoptions."
nuff said ?
I love linux, I've been using it for almost 15 years now, I absolutely hate iptables(and ipchains, and ipfwadm). By contrast I absolutely hate everything about OpenBSD except for pf(which I love, ipfw and ipf aren't too bad either, at least for the era), so I use OpenBSD for firewalls, and linux for everything else.
I can back this; during 2009, I deployed a bunch of load balancers running OpenBSD (using pf, carpd, and relayd). I used to be a super die hard BSD guy, but through the years and having used/deployed/propagated NetBSD, then FreeBSD, then OpenBSD, then NetBSD again, I took one of my usual once-a-year looks at GNU/Linux (this time, it was CentOS, after having worked with RHEL for some years), I got settled here.
Long story short: I'd really recommend OpenBSD for your task. iptables really sucks. I recently deployed some machines running several virtual instances (however still the cheapest *proven* way to get several IP stacks in Linux) doing L2 routing, I threw iptables off of that machines because it just can't handle stuff at that rate. OpenBSD rocks, I even have a setup running (active-active, load balanced) at about 40Mbps using Alix boards [0] -- they rock, and they are no way busy.
OpenBSDs documentation is the best out there, it's documentational quality is what I really really badly miss in the Linux world. However, the community is a bunch of (sorry in advance) assholes. But this is well known throughout the internet, so: You have been warned. Great product, totally lame vendor. ;)
Timo
[0] -- http://pcengines.ch/alix.htm
nate