Hi Horatiu It has been said a few times what the basic state machine should be in user space. A pure software solution can use raw sockets to send and receive MRP_Test test frames. When considering hardware acceleration, the switchdev API you have proposed here seems quite simple. It should not be too hard to map it to a set of netlink messages from userspace. Yet your argument for kernel, not user space, is you are worried about the parameters which need to be passed to the hardware offload engine. In order to win the argument for a kernel solution, we are going to need a better idea what you think this problem is. The MRP_Test is TLV based. Are there other things which could be in this message? Is that what you are worried about? Thanks Andrew