L3 Microkernel

Please note that the content of this book primarily consists of articles
available from Wikipedia or other free sources online. L3 is a
microkernel running on Intel's x86 computers. L3 is designed to be "very
lean and features fast, message-based, synchronous IPC, simple-to-use
external paging mechanisms and a security mechanism based on secure
domains (tasks, clans and chiefs)." It is the predecessor of L4, another
microkernel with similar design goals. L3 is also the name of a full
operating system based on the L3 microkernel. Both were developed by
Jochen Liedtke and his team at GMD's SET institute.