Circuit, Packet and Virtual-Circuit Switching
A network is a mesh of links and switches, and switching is the way data from one link is moved onto the next on its way to the destination. There are two fundamentally different answers.
Computer Networks · topic
Switching and performance metrics
Circuit, datagram and virtual-circuit switching compared on setup, path, order, sharing and header cost; message versus packet switching and the pipelining gain; transmission, propagation, queueing and processing delay, end-to-end delay over k links, throughput as the bottleneck rate, bandwidth-delay product, utilization, traffic intensity and the unit conventions (decimal rates, byte sizes).
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Network Performance Metrics: Delay, Throughput and BDP
Link and path performance is described by a few quantities: how long a packet takes to cross a link or a path (delay or latency), how many bits per second actually arrive (throughput), and how many bits are "in flight" on a path at once (the bandwidth-delay product).
Switching and performance metrics cheat sheets
One-page visual sheets for this topic, in the sheet library on the store. Previews are free; the full sheets come with the subject pack.