In a
network based on
packet switching
In telecommunications, packet switching is a method of grouping Data (computing), data into short messages in fixed format, i.e. ''network packet, packets,'' that are transmitted over a digital Telecommunications network, network. Packets consi ...
, processing delay is the time it takes
routers to process the
packet header. Processing delay is a key component in
network delay
Network delay is a design and performance characteristic of a telecommunications network. It specifies the latency for a bit of data to travel across the network from one communication endpoint to another. It is typically measured in multiple ...
.
During processing of a packet, routers may check for bit-level errors in the packet that occurred during transmission as well as determining where the packet's next destination is. Processing delays in high-speed routers are typically on the order of microseconds or less. After this nodal processing, the router directs the packet to the queue where further delay can happen (
queuing delay
In telecommunications and computer engineering, the queuing delay is the time a job waits in a queue until it can be executed. It is a key component of network delay. In a switched network, queuing delay is the time between the completion of si ...
).
In the past, the processing delay has been ignored as insignificant compared to the other forms of network delay. However, in some systems, the processing delay can be quite large especially where routers are performing complex encryption algorithms and examining or modifying packet content.
Ramaswamy Ramaswamy, Ning Weng and Tilman Wolf, ''Characterizing Network Processing Delay''
/ref> Deep packet inspection
Deep packet inspection (DPI) is a type of data processing that inspects in detail the data (Network packet, packets) being sent over a computer network, and may take actions such as alerting, blocking, re-routing, or logging it accordingly. Deep ...
done by some networks examine packet content for security, legal, or other reasons, which can cause very large delay and thus is only done at selected inspection points. Routers performing network address translation
Network address translation (NAT) is a method of mapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic Router (computing), routing device. The te ...
also have higher than normal processing delay because those routers need to examine and modify both incoming and outgoing packets.
See also
* Latency (engineering)
Latency, from a general point of view, is a time delay between the Causality, cause and the effect of some physical change in the system being observed. Lag (video games), Lag, as it is known in Gaming culture, gaming circles, refers to the late ...
References
Bibliography
*''Computer Networking: A Top-Down Approach'' by Kurose and Ross. 6th edition
Computer networking
Packets (information technology)
Computer engineering
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