latency

latency

(1) The time between initiating a request in the computer and receiving the answer. Data latency may refer to the time between a query and the results arriving at the screen or the time between initiating a transaction that modifies one or more databases and its completion.

Disk latency is the time it takes for the selected sector to be positioned under the read/write head. Channel latency is the time it takes for a computer channel to become unoccupied in order to transfer data. Network latency is the delay introduced when a packet is momentarily stored, analyzed and then forwarded.

(2) With malicious software, latency is the period between infection and the first obvious damage to the host system. Many viruses or logic bombs written by amateurs have a short latency and are therefore relatively easy to detect; however, more vicious malware can lie dormant or replicate to many other hosts and then wreak havoc unexpectedly. See logic bomb and virus.

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latency [′lat·ən·sē]

(computer science)

The waiting time between the order to read/write some information from/to a specified place and the beginning of the data-read/write operation.

(medicine)

The stage of an infectious disease, other than the incubation period, in which there are neither clinical signs nor symptoms.

(physiology)

The period between the introduction of and the response to a stimulus.

(psychology)

The phase between the Oedipal period and adolescence, characterized by an apparent cessation of psychosexual development.

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(communications)

latency - 1. The time it takes for a packet to cross a network connection, from sender to receiver. 2. The period of time that a frame is held by a network device before it is forwarded. Two of the most important parameters of a communications channel are its latency, which should be low, and its bandwidth, which should be high. Latency is particularly important for a synchronous protocol where each packet must be acknowledged before the next can be transmitted.