An Extensible Protocol Architecture for Application-Specific Networking

Abstract
Plexus is a networking architecture that allows applications to achieve high performance with customized protocols. Application-specific protocols are written in a typesafe language and installed dynamically into the operating system kernel. Because these protocols execute within the kernel, they can access the network interface and other operating system services with low overhead. Protocols implemented with Plexus outperform equivalent protocols implemented on conventional monolithic systems. Plexus runs in the context of the SPIN extensible operating system.

via An Extensible Protocol Architecture for Application-Specific Networking.