Networking

Networking code
Netfilter (cvs) (ml)
KAME (IPv6/IPsec networking stack implementation. License: BSD-style) (cvs)
vlan (802.1Q specification compliant "Virtual Local Area Network" implementation) (ml)
ULN ('User Level Networking' is a Linux kernel patch and a set of user-space tools to allow the dynamic allocation of IPv4/IPv6 addresses to different users) (cvs)
Tux (Kernelspace HTTP server)
tcpcp ("TCP Connection Passing". A mechanism to allow applications to pass ownership of TCP connection endpoints from one Linux host to another.) (ml)

IEEE 802.11 Wireless Networking Chipsets
IPv6 (Linux portal for the next generation of the Internet protocol)
FreeS/WAN (IPsec implementation) (ml)
MIPL (Mobile IPv6 for Linux) (ml)
OpenBT (Ericsson Bluetooth protocol stack developed by Axis) (ml)
BlueZ (Ericsson Bluetooth protocol stack) (cvs) (ml)
Affix (Ericsson Bluetooth protocol stack developed by Nokia) (cvs) (ml)
ATM ("Asyncronious Transfer Mode" information for Linux. ATM is a High-speed, non-broadcasting, physical network protocol.) (cvs) (ml)
STP ("Scheduled Transfer Protocol". An ANSI specified connection-oriented data transfer protocol for controlled high-bandwidth data transfer with minimal host CPU usage.) (ml)
Linux SCTP (Stream Control Transmission Protocol implementation) (cvs)
Token Ring
IPoCAN (GNU/Linux specific IP over CAN networking system) (cvs)
OpenSS7 (Project which tries to create a SS7 protocol stack for Linux and other Unices. Licensing Terms.)
isdn4linux (Linux ISDN driver framework and collection of ISDN related tools) (ml)
L2TP (Method for encapsulating standard PPP through a variety of media) (ml)
HyperSCSI (Networking protocol designed for the transmission of SCSI commands and data) (forum)
Linux DECnet (DECnet phase IV connectivity for Linux) (ml)

ECN (Explicit Congestion Notification. RFC 2481 standard implementation to help reduce wasted bandwidth in times of network congestion on routers.)
L7 (Linux kernel, iproute and tc patch to classify and prioritize packets based on patterns in in the application layer) (cvs) (ml)
Bandwidth Arbitrator (Linux kernel object and user-space tools to setup network traffic shaping) (ml)
HTB (QoS packet scheduler system, which can control the use of the outbound bandwidth on a given link. HTB is meant to be a better alternative to Linux CBQ qdisc.)