There's always something new and progressive in the free and open source software universe. Here's a roundup of some recent worthy happenings in the fun worlds of iptables and VoIP: getting SIP through iptables NAT firewalls, adding new modules to iptables with Patch-O-Matic, monitoring iptables in real-time, and a look at the excellent AstLinux, "the professional's PBX".
VoIP users have long struggled with getting SIP (Session Initiation Protocol) through NAT (Network Address Translation) firewalls. Good ole NAT, always gumming up the works. But, as usual, trusty hardworking devs ride to the rescue, and the SIP connection tracking module is ready for prime-time. It will be included in the 2.6.18 kernel. Meanwhile, if you don't mind a bit of patching and kernel-building you can have it now. To do this you need complete kernel sources (not just headers), a 2.6.11 kernel or newer, and iptables sources. Get the iptables sources from Netfilter.org.
