Linux Multilayer Switch

Linux Multilayer Switch is a crucial software that is part of a large project dedicated to constructing a Linux-based Layer 2 and 3 switching appliance. The ultimate goal is to have it integrated into the official Linux kernel, but this can only happen once the code reaches a certain level of maturity and is proved to be reliable to the kernel team.

This is not a standalone module but instead includes minor patches for the kernel networking code. As part of this project, we needed to hook into the packet reception code and the socket ioctl code to implement "deviceless" ioctl's on sockets. Additionally, there's a user space tool included to manage the kernel module's various features.

Linux Multilayer Switch's primary function is the implementation of ethernet layer 2 switching with VLAN (802.1q) support and VLAN virtual interfaces for inter-VLAN routing.

In the latest release, there's the addition of the Cisco Discovery Protocol, along with several bug fixes to both the userspace and kernel code. With this release, Linux Multilayer Switch has been updated to version 2.6.17, which has further improvements for better functionality. So if you're looking for a reliable Layer 2 and 3 switching appliance, Linux Multilayer Switch comes highly recommended.