The io_pkt Stack#

The io_pkt stack is very similar in architecture to other component subsystems inside of the Neutrino operating system. At the bottom layer, drivers exist which provide the mechanism for passing data to and receive data from hardware. The drivers hook into a multi-threaded layer 2 component (that also provides fast forwarding and bridging capability) that ties them together and provides a unified interface into the layer 3 component which then ties into the individual IP protocol processing components (TCP and UDP). In Neutrino, a resource manager is layered on top of the stack. The resource manager acts as the message passing intermediary between the stack and user applications. It provides a standardized open/read/write/ioctl type of interface using a message stream to communicate with networking applications. Networking applications in turn link with the socket library which converts the message passing interface exposed by the stack into a standard BSD style socket layer API.

Architecture#

Interfaces into the Stack#

Ether Input#

IP Input#

Layer 2 Bridging#