libioth

A network protocol stack can be implemented as a library. There are several examples: lwip/lwipv6, picoxnet, lkl. These libraries can be used to implement processes connected as network nodes (the so called "Internet of Thread" processes) or to implement network protocol stack servers for microkernels. The main goal of libioth is to provide a convenient API to interoperate with different network stack implementations. Libioth is also an infrastructure where the actual implementations can be loaded as plug-ins. Libioth's API is minimal: it includes the complete set of Berkeley Sockets functions, some functions to add or delete a stack and 'msocket', an extended version of 'socket' providing one more leading argument to select which stack should manage the communication. Libioth does not provide in its API any specific function to set up the network configuration, e.g. to configure the IP addresses/routes etc. These features are provided through netlink (see RFC3549). "nlinline" is a simple and effective set of inline functions to manage the network configuration. The data link layer infratructure used by libioth is VDE, Virtual Distributed Ethernet. Although libioth has been primarily designed for the Internet of Threads, the way it is used in the vunetioth module of vuos has many similarities with the network protocol stack servers for the microkernels. Several concepts and many building blocks of libioth can be useful in microkernel development. The design of the minimal API itself can be used to reuse existing stack implementations in network protocol stack servers. Libnlq (a sibling project of libioth) is a library able to process netlink requests, and can be used to add the netlink support to those stack implementations providing configuration through a custom specific API.