As systems become more distributed, especially with cloud computing environments, the network plays a bigger role in performance. Common tasks in network performance include improving network latency and throughput, and eliminating latency outliers, which can be caused by dropped or delayed packets.
Network analysis spans hardware and software. The hardware is the physical network, which includes the network interface cards, switches, routers, and gateways (these typically have software, too). The software is the kernel network stack including network device drivers, packet queues, and packet schedulers, and the implementation of network protocols. Lower-level protocols are typically kernel software (IP, TCP, UDP, etc.) and ...