We present the NBA framework, which extends the architecture of the Click modular router to exploit modern hardware, adapts to different hardware configurations, and reaches close to their maximum performance without manual optimization. NBA takes advantages of existing performance-excavating solutions such as batch processing, NUMA-aware memory management, and receiveside scaling with multi-queue network cards. Its abstraction resembles Click but also hides the details of architecturespecific optimization, batch processing that handles the path diversity of individual packets, CPU/GPU load balancing, and complex hardware resource mappings due to multi-core CPUs and multi-queue network cards. We have implemented four sample applications: an IPv4 and an IPv6 router, an IPsec encryption gateway, and an intrusion detection system (IDS) with Aho-Corasik and regular expression matching. The IPv4/IPv6 router performance reaches the line rate on a commodity 80 Gbps machine, and the performances of the IPsec gateway and the IDS reaches above 30 Gbps. We also show that our adaptive CPU/GPU load balancer reaches near-optimal throughput in various combinations of sample applications and traffic conditions.

We propose and evaluate RoCE (RDMA over Converged Ethernet) as a low-latency back-plane for horizontally scaled software router nodes. By exploring combinations of design choices in developing internal fabric for software routers, we select a set of parameters and packet I/O APIs that yield the lowest latency and highest throughput. Using the optimal settings derived, we measure and compare latency and throughput of an RoCE interconnect against Ethernet using a high-performance userspace network driver (Intel DPDK). Our comparison shows that RoCE keeps low latency in all packet sizes while it has throughput penalties for network workloads (e.g., small packet sizes). To mitigate throughput penalties imposed by guaranteeing low latency, we suggest a hardware-assisted, batched forwarding scheme based on scatter-and-gather functionality of RDMAcapable NICs. When forwarding ingress network packets, our scheme achieves comparable to or higher throughput then Ethernet at the cost of several microseconds of latency.