P4Tune: Enabling Programmability in Non-Programmable Networks

Abstract

Data plane programmability has attracted significant attention, permitting network operators to run customized packet processing functions. Unfortunately, networks today are still largely dominated by proprietary fixed-function devices. It is challenging for operators to completely migrate to programmable data planes (PDPs) due to the economical costs of replacing equipment and limited expertise in maintaining and operating programmable networks. This article introduces P4Tune, a cost-efficient architecture that uses passive PDPs coupled with optical taps. P4Tune runs customized packet processing functions operating at line rate and collects network information with nanosecond resolution. This visibility enables intelligent algorithms residing in the control plane to construct configuration rules and apply them on the legacy devices, thus creating a closed control loop. P4Tune brings the benefits of processing traffic at line rate to legacy networks. Additionally, by using PDPs passively, the architecture can be safely deployed without disrupting current network operations, fostering incremental use of PDPs (i.e., no need to deploy complex code at once). The article demonstrates three applications of the proposed architecture related to Quality of Service (QoS) and cybersecurity.