Packet switch

A packet switch is a node in a network which uses the packet switching paradigm for data communication. Packet switches can operate at a number of different levels in a protocol suite; although the exact technical details differ, fundamentally they all perform the same function: they store and forward packets.

One common class of contemporary packet switches are the bridge and network hub, which interconnect multiple network segments at the data link layer. Another is the router, a device which operates at the internetwork layer, and connects dissimilar kinds of networks, such as serial lines and local area networks.

Generally, packet switches only perform communication-related functions, but in some systems the computers which performed the packet-switching function were also used for data storage and computation.

Originally, packet switches were built around standard minicomputers. Today, almost all packet switches are specialized hardware devices, ranging in size and performance from small local hubs up to the large switching systems used by major Internet service providers. However, software is available which allows a personal computer to function as a low-performance packet switch.