Linux Intermediate Queueing (IMQ) Device
- Software used to implement egress+ingress traffic control over multiple interfaces using the usual egress qdiscs.
- http://www.linuximq.net/

PoPToP
- Point-to-point tunnelling protocol server for linux. Allows Linux machines to operate PPTP VPNs with Windows 2000 machines.
- http://www.poptop.org/

Linux Virtual Server Project - Linux Server Cluster
- The Linux Virtual Server is a highly scalable and highly available server built on a cluster of real servers, with the load balancer running on the Linux operating system. The architecture of the cluster is transparent to end users.
- http://www.linuxvirtualserver.org/

LKSCTP - Linux Kernel Stream Control Transmission Protocol
- The Linux Kernel Stream Control Transmission Protocol (lksctp) project is an implementation of the Stream Control Transmission Protocol (SCTP) in the Linux kernel.
- http://lksctp.sourceforge.net

SNIPS - System and Network Management Monitoring Software
- SNIPS/NOCOL systems and network monitoring software.
- http://www.netplex-tech.com/snips/

Nagios - Network Monitoring Software
- An open source host, service, and network monitoring program.
- http://www.nagios.org/

UnWiredAP
- UnWiredAP is a Linux-based floppy distribution with support for Prism 2 & 2.5 WLAN cards.
- http://unwiredap.sourceforge.net/

PPTP Masquerading Page
- Kernel module to allow Linux IP masquerading to handle PPTP.
- http://bmrc.berkeley.edu/people/chaffee/linux_pptp.html

FreeS/WAN Project
- The FreeS/WAN project provides a free VPN solution for the Linux platform, allowing users to create an IPSEC/3DES virtual private network.
- http://www.freeswan.org/

Samba Project
- SMB Server for Linux that allows a Linux machine to connect and share files with a Windows machine and/or Windows-based network.
- http://www.samba.org/

Netfilter / IPTABLES
- The kernel level firewalling system in Linux 2.4. This site contains the source and documentation for the kernel-space code and user-space utilities.
- http://netfilter.samba.org/