CHANOS is an open source and Linux-based multi-layer network operating system(NOS). It can be run on all kinds of ethernet switchs such as standard pizzabox or stackable box or chassis. Now it is running well with Marvell/Broadcom/Qualcomm/Centec chipsets and SDKs. It also very easy to be ported to many kinds of CPUs including Cavium's multi-core MIPS, Chinese Loongson, Marvell Armada and etc. Major components of CHANOS run in user space.