This document describes a new networking subsystem architecture built around a packet classifier executing in the Network Interface Card (NIC). By classifying packets in the NIC, we believe that performance, scalability, and robustness can be significantly improved on shared-memory multiprocessor Internet servers. In order to demonstrate the feasibility and the benefits of the approach, we developed a software prototype (consisting in extensions to the Linux kernel and modifications to the Myrinet NIC firmware and driver) and ran a series of experiments. The obtained results, presented therein, show the relevance of the approach.