packet mode

Packet switching is a communications paradigm in which packets (discrete blocks of data) are  routed between nodes over data links shared with other traffic. In each network node, packets are queued or buffered, resulting in variable delay. This contrasts with the other principal paradigm, circuit switching, which sets up limited number of constant bit rate and constant delay connections between the nodes for their exclusive use for the duration of the communication.
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A mode of operating a communications network in which packet switching is used rather than message switching. [From Weik '89]