Kernel and Microkernel

The Routing Engine kernel provides the underlying infrastructure for all JUNOS software processes by doing the following:

• Linking the routing tables maintained by the routing protocol process with the forwarding table maintained by the Routing Engine.
• Coordinating communication with the Packet Forwarding Engine, primarily by synchronizing the Packet Forwarding Engine’s forwarding table with the master forwarding table maintained by the Routing Engine.

The microkernel contains device drivers and processes that the Packet Forwarding Engine uses to govern the flow of packets through the Services Router.