Architectural impact of stateful networking applications

The explosive and robust growth of the Internet owes a lot to the "end-to-end principle", which pushes stateful operations to the end-points. The Internet grew both in traffic volume, and in the richness of the applications it supports. The growth also brought along new security issues and network monitoring applications. Edge devices, in particular, tend to perform upper layer packet processing. A whole new class of applications require stateful processing. In this paper we study the impact of stateful networking applications on architectural bottlenecks. The analysis covers applications with a variety of statefulness levels. The study emphasizes the data cache behavior. Nevertheless, we also discuss other issues, such as branch prediction and ILP. Additionally, we analyze the architectural impact through the TCP connection life. Our results show an important memory bottleneck due to maintaining the states. Moreover, depending on the target of the application, the memory bottleneck may be concentrated within a set of packets or distributed along the TCP connection lifetime.