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In general terms, throughput is the rate of production or the rate at which something is processed. When used in the context of communication networks, such as
Ethernet Ethernet () is a family of wired ing technologies commonly used in s (LAN), s (MAN) and s (WAN). It was commercially introduced in 1980 and first standardized in 1983 as . Ethernet has since been refined to support higher s, a greater number ...

Ethernet
or
packet radio Packet radio is a digital radio Digital radio is the use of digital technology to transmit or receive across the radio spectrum. Digital transmission by radio waves includes digital broadcasting, and especially digital audio radio services. Ty ...
, throughput or network throughput is the rate of ''successful'' message delivery over a communication channel. The data these messages belong to may be delivered over a physical or logical link, or it can pass through a certain
network nodeIn telecommunications network A telecommunications network is a group of nodes interconnected by links that are used to exchange messages between the nodes. The links may use a variety of technologies based on the methodologies of circuit switchi ...
. Throughput is usually measured in
bits per second In telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio, Optical system, optical, or other Electromagnetism, electromagnetic systems. It has its origin in the desire of huma ...
(bit/s or bps), and sometimes in data packets per second (p/s or pps) or data packets per
time slot Broadcast programming is the practice of organizing and/or ordering (scheduling) of broadcast Broadcasting is the distribution (business), distribution of sound, audio or video content to a dispersed audience via any electronic medium (commun ...
. The system throughput or aggregate throughput is the sum of the data rates that are delivered to all terminals in a network. Throughput is essentially synonymous to digital bandwidth consumption; it can be analyzed mathematically by applying the
queueing theory Queueing theory is the mathematical study of waiting lines, or . A queueing model is constructed so that queue lengths and waiting time can be predicted. Queueing theory is generally considered a branch of because the results are often used whe ...
, where the load in packets per time unit is denoted as the arrival rate (), and the throughput, where the drop in packets per time unit, is denoted as the departure rate (). The throughput of a communication system may be affected by various factors, including the limitations of underlying analog physical medium, available processing power of the system components, and
end-user In product development, an end user (sometimes end-user) is a person who ultimately uses or is intended to ultimately use a product. The end user stands in contrast to users who support or maintain the product, such as sysops, system administrator ...
behavior. When various protocol overheads are taken into account, useful rate of the transferred data can be significantly lower than the maximum achievable throughput; the useful part is usually referred to as
goodput In computer networks, goodput (a of and ) is the throughput of a communication; i.e. the number of useful information s delivered by the network to a certain destination per unit of time. The amount of data considered excludes bits as well as ...
.


Maximum throughput

Users of telecommunications devices, systems designers, and researchers into communication theory are often interested in knowing the expected performance of a system. From a user perspective, this is often phrased as either "which device will get my data there most effectively for my needs?", or "which device will deliver the most data per unit cost?". Systems designers are often interested in selecting the most effective architecture or design constraints for a system, which drive its final performance. In most cases, the benchmark of what a system is capable of, or its "maximum performance" is what the user or designer is interested in. When examining throughput, the term ''maximum throughput'' is frequently used where end-user maximum throughput tests are discussed in detail. Maximum throughput is essentially synonymous to digital bandwidth capacity. Four different values have meaning in the context of "maximum throughput", used in comparing the 'upper limit' conceptual performance of multiple systems. They are 'maximum theoretical throughput', 'maximum achievable throughput', and 'peak measured throughput' and 'maximum sustained throughput'. These represent different quantities and care must be taken that the same definitions are used when comparing different 'maximum throughput' values. Comparing throughput values is also dependent on each bit carrying the same amount of information.
Data compression In signal processing Signal processing is an electrical engineering subfield that focuses on analysing, modifying, and synthesizing signals such as audio signal processing, sound, image processing, images, and scientific measurements. Signal ...
can significantly skew throughput calculations, including generating values greater than 100%. If the communication is mediated by several links in series with different bit rates, the maximum throughput of the overall link is lower than or equal to the lowest bit rate. The lowest value link in the series is referred to as the
bottleneck Bottleneck literally refers to the narrowed portion (neck) of a bottle A bottle is a narrow-necked container made of an impermeable material (clay, glass Glass is a non- crystalline, often transparency and translucency, transparent amorpho ...
.


Maximum theoretical throughput

This number is closely related to the
channel capacity Channel capacity, in electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It em ...
of the system, and is the maximum possible quantity of data that can be transmitted under ideal circumstances. In some cases this number is reported as equal to the channel capacity, though this can be deceptive, as only non-packetized systems (asynchronous) technologies can achieve this without data compression. Maximum theoretical throughput is more accurately reported to take into account format and specification overhead with best case assumptions. This number, like the closely related term 'maximum achievable throughput' below, is primarily used as a rough calculated value, such as for determining bounds on possible performance early in a system design phase


Asymptotic throughput

The asymptotic throughput (less formal ''asymptotic bandwidth'') for a packet-mode
communication network A telecommunications network is a group of nodes In general, a node is a localized swelling (a "knot") or a point of intersection (a Vertex (graph theory), vertex). Node may refer to: In mathematics *Vertex (graph theory), a vertex in a mathema ...
is the value of the
maximum throughput In general terms, throughput is the rate of production or the rate at which something is processed. When used in the context of communication networks, such as Ethernet Ethernet () is a family of wired computer network A computer net ...
function, when the incoming network load approaches
infinity Infinity is that which is boundless, endless, or larger than any number A number is a mathematical object A mathematical object is an abstract concept arising in mathematics. In the usual language of mathematics, an ''object'' is anything ...

infinity
, either due to a message size as it approaches
infinity Infinity is that which is boundless, endless, or larger than any number A number is a mathematical object A mathematical object is an abstract concept arising in mathematics. In the usual language of mathematics, an ''object'' is anything ...

infinity
, or the number of data sources is very large. As other
bit rate In telecommunications and computing, bit rate (bitrate or as a variable ''R'') is the number of bits that are conveyed or processed per unit of time. The bit rate is expressed in the unit Data rate units, bit per second unit (symbol: ''bit/s'' ...
s and
data bandwidth In computing, bandwidth is the maximum rate of data transfer across a given path. Bandwidth may be characterized as network bandwidth, data bandwidth, or digital bandwidth. This definition of ''bandwidth'' is in contrast to the field of signal proc ...
s, the asymptotic throughput is measured in
bits per second In telecommunications Telecommunication is the transmission of information by various types of technologies over wire, radio, Optical system, optical, or other Electromagnetism, electromagnetic systems. It has its origin in the desire of huma ...
(bit/s), very seldom
byte The byte is a unit of digital information that most commonly consists of eight bit The bit is a basic unit of information in computing Computing is any goal-oriented activity requiring, benefiting from, or creating computing machinery. It ...
s per second (B/s), where 1 B/s is 8 bit/s.
Decimal prefix A metric prefix is a unit prefix A unit prefix is a specifier or mnemonic that is prepended to units of measurement to indicate multiples or fractions of the units. Units of various order of magnitude, sizes are commonly formed by the use of such ...
es are used, meaning that 1 Mbit/s is 1000000 bit/s. Asymptotic throughput is usually estimated by sending or simulating a very large message (sequence of data packets) through the network, using a
greedy sourceA greedy source is a traffic generator that generates data at the maximum rate possible and at the earliest opportunity possible. Each source always has data to transmit, and is never in idle state due to congestion avoidance or other local host tr ...
and no flow control mechanism (i.e.
UDP UDP may refer to: Political parties * Ulster Democratic Party, in Northern Ireland * ''União Democrática Popular'' (People's Democratic Union (Portugal)) * ''Unidad Democrática y Popular'' (Democratic and Popular Union), a former Bolivian umbr ...
rather than TCP), and measuring the network path throughput in the destination node. Traffic load between other sources may reduce this maximum network path throughput. Alternatively, a large number of sources and sinks may be modeled, with or without flow control, and the aggregate maximum network throughput measured (the sum of traffic reaching its destinations). In a network simulation model with infinite packet queues, the asymptotic throughput occurs when the
latency Latency or latent may refer to: Science and technology * Latent heat, energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process * Latent variable, a variable that is not directly observed but inferred i ...
(the packet queuing time) goes to infinity, while if the packet queues are limited, or the network is a multi-drop network with many sources, and collisions may occur, the packet-dropping rate approaches 100%. A well known application of asymptotic throughput is in modeling
point-to-point communication Point-to-point, point to point, or port to port may refer to: Technology * Point-to-point construction Point-to-point construction is a non-automated method of construction of widely used before the use of s (PCBs) and automated assembly gra ...
where (following Hockney) message latency T(N) is modeled as a function of message length N as T(N) = (M + N)/A where A is the asymptotic bandwidth and M is the half-peak length. As well as its use in general network modeling, asymptotic throughput is used in modeling performance on
massively parallel Massively parallel is the term for using a large number of computer A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations automatically. Modern computers can perform generic sets of opera ...
computer systems, where system operation is highly dependent on communication overhead, as well as processor performance. In these applications, asymptotic throughput is used in Xu and Hwang model (more general than Hockney's approach) which includes the number of processors, so that both the latency and the asymptotic throughput are functions of the number of processors.


Peak measured throughput

The above values are theoretical or calculated. Peak measured throughput is throughput measured by a real, implemented system, or a simulated system. The value is the throughput measured over a short period of time; mathematically, this is the limit taken with respect to throughput as time approaches zero. This term is synonymous with ''instantaneous throughput''. This number is useful for systems that rely on burst data transmission; however, for systems with a high
duty cycle File:Duty-Cycle-and-Spectrum.ogv, Spectrum in relation to duty cycle A duty cycle or power cycle is the fraction of one Frequency, period in which a signal or system is active. Duty cycle is commonly expressed as a percentage or a ratio. A period ...
this is less likely to be a useful measure of system performance.


Maximum sustained throughput

This value is the throughput averaged or integrated over a long time (sometimes considered infinity). For high duty cycle networks this is likely to be the most accurate indicator of system performance. The maximum throughput is defined as the asymptotic throughput when the load (the amount of incoming data) is very large. In
packet switched In telecommunication Telecommunication is the transmission of information Information can be thought of as the resolution of uncertainty; it answers the question of "What an entity is" and thus defines both its essence and the nature of ...
systems where the load and the throughput always are equal (where
packet loss Packet loss occurs when one or more packet (information technology), packets of data travelling across a computer network fail to reach their destination. Packet loss is either caused by errors in data transmission, typically across wireless netw ...

packet loss
does not occur), the maximum throughput may be defined as the minimum load in bit/s that causes the delivery time (the
latency Latency or latent may refer to: Science and technology * Latent heat, energy released or absorbed, by a body or a thermodynamic system, during a constant-temperature process * Latent variable, a variable that is not directly observed but inferred i ...
) to become unstable and increase towards infinity. This value can also be used deceptively in relation to peak measured throughput to conceal packet shaping.


Channel utilization and efficiency

Throughput is sometimes normalized and measured in percentage, but normalization may cause confusion regarding what the percentage is related to. ''Channel utilization'', ''channel efficiency'' and ''packet drop rate'' in percentage are less ambiguous terms. The channel efficiency, also known as bandwidth utilization efficiency, is the percentage of the
net bit rate In telecommunications Telecommunication is the transmission of information Information can be thought of as the resolution of uncertainty; it answers the question of "What an entity is" and thus defines both its essence and the natur ...
(in bit/s) of a digital
communication channel A communication channel refers either to a physical transmission medium A transmission medium is a system or substance that can mediate the propagation of signal In signal processing Signal processing is an electrical engineering ...
that goes to the actually achieved throughput. For example, if the throughput is 70 Mbit/s in a 100 Mbit/s Ethernet connection, the channel efficiency is 70%. In this example, effective 70 Mbit of data are transmitted every second. Channel utilization is instead a term related to the use of the channel disregarding the throughput. It counts not only with the data bits but also with the overhead that makes use of the channel. The transmission overhead consists of preamble sequences, frame headers and acknowledge packets. The definitions assume a noiseless channel. Otherwise, the throughput would not be only associated to the nature (efficiency) of the protocol but also to retransmissions resultant from quality of the channel. In a simplistic approach, channel efficiency can be equal to channel utilization assuming that acknowledge packets are zero-length and that the communications provider will not see any bandwidth relative to retransmissions or headers. Therefore, certain texts mark a difference between channel utilization and protocol efficiency. In a point-to-point or
point-to-multipoint communication In telecommunications, point-to-multipoint communication (P2MP, PTMP or PMP) is communication which is accomplished via a distinct type of one-to-many connection, providing multiple paths from a single location to multiple locations. Point-to-mu ...
link, where only one terminal is transmitting, the maximum throughput is often equivalent to or very near the physical data rate (the
channel capacity Channel capacity, in electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics, and electromagnetism. It em ...
), since the channel utilization can be almost 100% in such a network, except for a small inter-frame gap. For example, the maximum frame size in Ethernet is 1526 bytes: up to 1500 bytes for the payload, eight bytes for the preamble, 14 bytes for the header, and 4 bytes for the trailer. An additional minimum interframe gap corresponding to 12 bytes is inserted after each frame. This corresponds to a maximum channel utilization of 1526 / (1526 + 12) × 100% = 99.22%, or a maximum channel use of 99.22 Mbit/s inclusive of Ethernet datalink layer protocol overhead in a 100 Mbit/s Ethernet connection. The maximum throughput or channel efficiency is then 1500 / (1526 + 12) = 97.5%, exclusive of the Ethernet protocol overhead.


Factors affecting throughput

The throughput of a communication system will be limited by a huge number of factors. Some of these are described below:


Analog limitations

The maximum achievable throughput (the channel capacity) is affected by the bandwidth in hertz and
signal-to-noise ratio Signal-to-noise ratio (SNR or S/N) is a measure used in science and engineering Engineering is the use of scientific principles to design and build machines, structures, and other items, including bridges, tunnels, roads, vehicles, and ...
of the analog physical medium. Despite the conceptual simplicity of digital information, all electrical signals traveling over wires are analog. The analog limitations of wires or wireless systems inevitably provide an upper bound on the amount of information that can be sent. The dominant equation here is the Shannon-Hartley theorem, and analog limitations of this type can be understood as factors that affect either the analog bandwidth of a signal or as factors that affect the signal-to-noise ratio. The bandwidth of wired systems can be in fact surprisingly narrow, with the bandwidth of Ethernet wire limited to approximately 1 GHz, and PCB traces limited by a similar amount. Digital systems refer to the 'knee frequency', the amount of time for the digital voltage to rise from 10% of a nominal digital '0' to a nominal digital '1' or vice versa. The knee frequency is related to the required bandwidth of a channel, and can be related to the 3 db bandwidth of a system by the equation: \ F_ \approx K/T_r Where Tr is the 10% to 90% rise time, and K is a constant of proportionality related to the pulse shape, equal to 0.35 for an exponential rise, and 0.338 for a Gaussian rise. *RC losses: wires have an inherent resistance, and an inherent
capacitance Capacitance is the ratio of the amount of stored on a to a difference in . There are two closely related notions of capacitance: ''self capacitance'' and ''mutual capacitance''. Any object that can be electrically charged exhibits ''self capa ...
when measured with respect to ground. This leads to effects called
parasitic capacitance Parasitic capacitance, or stray capacitance is an unavoidable and usually unwanted capacitance Capacitance is the ratio of the amount of electric charge Electric charge is the physical property of matter that causes it to experience a force ...
, causing all wires and cables to act as RC lowpass filters. *
Skin effect Skin effect is the tendency of an alternating electric current (AC) to become distributed within a conductor Conductor or conduction may refer to: Music * Conductor (music), a person who leads a musical ensemble like, for example, an or ...

Skin effect
: As frequency increases, electric charges migrate to the edges of wires or cable. This reduces the effective cross-sectional area available for carrying current, increasing resistance and reducing the signal-to-noise ratio. For AWG 24 wire (of the type commonly found in Cat 5e cable), the skin effect frequency becomes dominant over the inherent resistivity of the wire at 100 kHz. At 1 GHz the resistivity has increased to 0.1 ohms/inch. *Termination and ringing: For long wires (wires longer than 1/6 wavelengths can be considered long) must be modeled as
transmission line In electrical engineering Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems which use electricity, electronics The field of electronics is a branch o ...

transmission line
s and take termination into account. Unless this is done, reflected signals will travel back and forth across the wire, positively or negatively interfering with the information-carrying signal. * Wireless Channel Effects: For wireless systems, all of the effects associated with wireless transmission limit the SNR and bandwidth of the received signal, and therefore the maximum number of bits that can be sent.


IC hardware considerations

Computational systems have finite processing power, and can drive finite current. Limited current drive capability can limit the effective signal to noise ratio for high
capacitance Capacitance is the ratio of the amount of stored on a to a difference in . There are two closely related notions of capacitance: ''self capacitance'' and ''mutual capacitance''. Any object that can be electrically charged exhibits ''self capa ...
links. Large data loads that require processing impose data processing requirements on hardware (such as routers). For example, a gateway router supporting a populated class B subnet, handling 10 x 100 Mbit/s Ethernet channels, must examine 16 bits of address to determine the destination port for each packet. This translates into 81913 packets per second (assuming maximum data payload per packet) with a table of 2^16 addresses this requires the router to be able to perform 5.368 billion lookup operations per second. In a worst-case scenario, where the payloads of each Ethernet packet are reduced to 100 bytes, this number of operations per second jumps to 520 billion. This router would require a multi-teraflop processing core to be able to handle such a load. *
CSMA/CD Carrier-sense multiple access with collision detection (CSMA/CD) is a media access control (MAC) method used most notably in early Ethernet technology for local area networking. It uses Carrier signal, carrier-sensing to defer transmissions until no ...
and
CSMA/CA Carrier-sense multiple access with collision avoidance (CSMA/CA) in computer networking, is a network multiple access method in which Carrier signal, carrier sensing is used, but Node (networking), nodes attempt to avoid collisions by beginning tra ...
"backoff" waiting time and frame retransmissions after detected collisions. This may occur in Ethernet bus networks and hub networks, as well as in wireless networks. * flow control, for example in the
Transmission Control Protocol The Transmission Control Protocol (TCP) is one of the main protocols of the Internet protocol suite The Internet protocol suite, commonly known as TCP/IP, is the set of communications protocol A communication protocol is a system of rules ...
(TCP) protocol, affects the throughput if the
bandwidth-delay product In data communications, the bandwidth-delay product is the Multiplication, product of a data link's capacity (in Bit rate, bits per second) and its round-trip delay time (in seconds). The result, an amount of data measured in bits (or bytes), is ...
is larger than the TCP window, i.e. the buffer size. In that case the sending computer must wait for acknowledgement of the data packets before it can send more packets. * TCP
congestion avoidance Congestion may refer to: Medicine *Excessive fluid in tissues, vessels, or both, including: ** Edema, abnormal accumulation of fluid in the interstitium, manifesting as swelling *** Peripheral edema, edema in peripheral body parts such as limbs ...
controls the data rate. So called "slow start" occurs in the beginning of a file transfer, and after packet drops caused by router congestion or bit errors in for example wireless links.


Multi-user considerations

Ensuring that multiple users can harmoniously share a single communications link requires some kind of equitable sharing of the link. If a bottle neck communication link offering data rate ''R'' is shared by "N" active users (with at least one data packet in queue), every user typically achieves a throughput of approximately ''R/N'', if
fair queuing Fair queuing is a family of scheduling algorithms used in some process and network schedulers. The algorithm is designed to achieve fairness when a limited resource is shared, for example to prevent flows with large packets or processes that gen ...
best-effort Best-effort delivery describes a network service in which the Wiktionary:Network, network does not provide any guarantee that data is delivered or that delivery meets any quality of service. In a best-effort network, all users obtain best-effort ser ...
communication is assumed. *
Packet loss Packet loss occurs when one or more packet (information technology), packets of data travelling across a computer network fail to reach their destination. Packet loss is either caused by errors in data transmission, typically across wireless netw ...

Packet loss
due to
Network congestion Network congestion in data networking A computer network is a set of computers sharing resources located on or provided by Node (networking), network nodes. The computers use common communication protocols over digital signal, digital Interc ...
. Packets may be dropped in switches and routers when the packet queues are full due to congestion. * Packet loss due to
bit error In digital transmission, the number of bit errors is the number of received bits of a data stream over a communication channel that have been altered due to noise (telecommunications), noise, interference (communication), interference, distortio ...
s. * Scheduling algorithms in routers and switches. If fair queuing is not provided, users that send large packets will get higher bandwidth. Some users may be prioritized in a
weighted fair queuing Weighted fair queueing (WFQ) is a network scheduling algorithm. WFQ is both a packet-based implementation of the generalized processor sharing (GPS) policy, and a natural extension of fair queuing (FQ). Whereas FQ shares the link's capacity in eq ...
(WFQ) algorithm if differentiated or guaranteed
quality of service Quality of service (QoS) is the description or measurement of the overall performance of a service, such as a telephony Telephony ( ) is the field of technology involving the development, application, and deployment of telecommunication Tel ...
(QoS) is provided. * In some communications systems, such as satellite networks, only a finite number of channels may be available to a given user at a given time. Channels are assigned either through preassignment or through Demand Assigned Multiple Access (DAMA).Roddy, 2001, 370 - 371 In these cases, throughput is quantized per channel, and unused capacity on partially utilized channels is lost..


Goodput and overhead

The maximum throughput is often an unreliable measurement of perceived bandwidth, for example the file transmission data rate in bits per seconds. As pointed out above, the achieved throughput is often lower than the maximum throughput. Also, the protocol overhead affects the perceived bandwidth. The throughput is not a well-defined metric when it comes to how to deal with protocol overhead. It is typically measured at a reference point below the network layer and above the physical layer. The most simple definition is the number of bits per second that are physically delivered. A typical example where this definition is practiced is an Ethernet network. In this case the maximum throughput is the
gross bit rate In telecommunications and computing, bit rate (bitrate or as a variable ''R'') is the number of bits that are conveyed or processed per unit of time. The bit rate is expressed in the unit Data rate units, bit per second unit (symbol: ''bit/s'' ...
or raw bit rate. However, in schemes that include forward error correction codes (channel coding), the redundant error code is normally excluded from the throughput. An example in
modem A modulator-demodulator, or simply a modem, is a hardware device that converts data from a digital format, intended for communication directly between devices with specialized wiring, into one suitable for a transmission medium such as telep ...

modem
communication, where the throughput typically is measured in the interface between the
Point-to-Point Protocol In computer networking, Point-to-Point Protocol (PPP) is a data link layer (layer 2) communication protocol between two routers directly without any host or any other networking in between. It can provide connection authentication, transmission e ...
(PPP) and the circuit-switched modem connection. In this case the maximum throughput is often called
net bit rate In telecommunications Telecommunication is the transmission of information Information can be thought of as the resolution of uncertainty; it answers the question of "What an entity is" and thus defines both its essence and the natur ...
or useful bit rate. To determine the actual data rate of a network or connection, the "
goodput In computer networks, goodput (a of and ) is the throughput of a communication; i.e. the number of useful information s delivered by the network to a certain destination per unit of time. The amount of data considered excludes bits as well as ...
" measurement definition may be used. For example, in file transmission, the "goodput" corresponds to the file size (in bits) divided by the file transmission time. The "
goodput In computer networks, goodput (a of and ) is the throughput of a communication; i.e. the number of useful information s delivered by the network to a certain destination per unit of time. The amount of data considered excludes bits as well as ...
" is the amount of useful information that is delivered per second to the
application layer An application layer is an abstraction layer that specifies the shared communications protocols and Interface (computing), interface methods used by Host (network), hosts in a communications network. The application layer abstraction is used in b ...
protocol. Dropped packets or packet retransmissions, as well as protocol overhead, are excluded. Because of that, the "goodput" is lower than the throughput. Technical factors that affect the difference are presented in the "
goodput In computer networks, goodput (a of and ) is the throughput of a communication; i.e. the number of useful information s delivered by the network to a certain destination per unit of time. The amount of data considered excludes bits as well as ...
" article.


Other uses of throughput for data


Integrated circuits

Often, a block in a
data flow diagram A data-flow diagram is a way of representing a flow of data through a process or a system (usually an information system An information system (IS) is a formal, sociotechnical, organizational system designed to collect, process, store, and distribu ...
has a single input and a single output, and operate on discrete packets of information. Examples of such blocks are
Fast Fourier Transform A fast Fourier transform (FFT) is an algorithm that computes the discrete Fourier transform (DFT) of a sequence, or its inverse (IDFT). Fourier analysis converts a signal from its original domain (often time or space) to a representation in t ...
modules or
binary multiplier A binary multiplier is an electronic circuit File:PExdcr01CJC.jpg, 200px, A circuit built on a printed circuit board (PCB). An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors ...

binary multiplier
s. Because the units of throughput are the reciprocal of the unit for
propagation delay Propagation delay is the length of time taken for a signal to reach its destination. It can relate to networking, electronics Electronics comprises the physics, engineering, technology and applications that deal with the emission, flow and con ...
, which is 'seconds per message' or 'seconds per output', throughput can be used to relate a computational device performing a dedicated function such as an
ASIC An application-specific integrated circuit (ASIC ) is an integrated circuit An integrated circuit or monolithic integrated circuit (also referred to as an IC, a chip, or a microchip) is a set of electronic circuit 200px, A circuit b ...
or
embedded processor An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' ...
to a communications channel, simplifying system analysis.


Wireless and cellular networks

In
wireless network A wireless network is a computer network A computer network is a set of s sharing resources located on or provided by . The computers use common s over to communicate with each other. These interconnections are made up of technologies, ...

wireless network
s or cellular systems, the
system spectral efficiency Spectral efficiency, spectrum efficiency or bandwidth efficiency refers to the information rate that can be transmitted over a given bandwidth in a specific communication system. It is a measure of how efficiently a limited frequency spectrum is u ...
in bit/s/Hz/area unit, bit/s/Hz/site or bit/s/Hz/cell, is the maximum system throughput (aggregate throughput) divided by the analog bandwidth and some measure of the system coverage area.


Over analog channels

Throughput over analog channels is defined entirely by the modulation scheme, the signal to noise ratio, and the available bandwidth. Since throughput is normally defined in terms of quantified digital data, the term 'throughput' is not normally used; the term 'bandwidth' is more often used instead.


See also

* BWPing *
Greedy sourceA greedy source is a traffic generator that generates data at the maximum rate possible and at the earliest opportunity possible. Each source always has data to transmit, and is never in idle state due to congestion avoidance or other local host tr ...
*
High-throughput computing High-throughput computing (HTC) is a computer science term to describe the use of many computing resources over long periods of time to accomplish a computational task. Challenges The HTC community is also concerned with robustness and reliability ...
(HTC) *
Iperf Iperf is a tool for network performanceNetwork performance refers to measures of service quality of a network as seen by the customer. There are many different ways to measure the performance of a network, as each network is different in nature ...

Iperf
*
Measuring network throughput Throughput In general terms, throughput is the rate of production or the rate at which something is processed. When used in the context of communication networks, such as Ethernet or packet radio, throughput or network throughput is the rat ...
*
Network traffic measurementIn computer networks, network traffic measurement is the process of measuring the amount and type of traffic on a particular network. This is especially important with regard to effective bandwidth management. Techniques Network performance could ...
*
Performance engineering Performance engineering encompasses the techniques applied during a systems development life cycle to ensure the non-functional requirements for performance (such as throughput In general terms, throughput is the rate of production or the rate ...

Performance engineering
*
Traffic generation model A traffic generation model is a stochastic model of the traffic flows or data sources in a communication network, for example a cellular network or a computer network. A packet generation model is a traffic generation model of the packet flows o ...
*
ttcp The program ttcp (Test Transmission Control Protocol, TCP) is a utility for measuring network throughput, popular on Unix systems. It measures the network throughput between two systems using the Transmission Control Protocol, TCP or optionally ...


References


Further reading

* Rappaport, Theodore S. ''Wireless Communications, Principles and Practice'' second edition,
Prentice Hall Prentice Hall is an American major educational publisher owned by Savvas Learning Company. Prentice Hall publishes print and digital content for the 6–12 and higher-education market. Prentice Hall distributes its technical titles through th ...
, 2002, * Blahut, Richard E. ''Algebraic Codes for Data Transmission''
Cambridge University Press Cambridge University Press (CUP) is the publishing business of the University of Cambridge , mottoeng = Literal: From here, light and sacred draughts. Non literal: From this place, we gain enlightenment and precious knowled ...
, 2004, * Li, Harnes, Holte, "Impact of Lossy Links on Performance of Multihop Wireless Networks", IEEE, Proceedings of the 14th International Conference on Computer Communications and Networks, Oct 2005, 303 - 308 * Johnson, Graham, ''High Speed Digital Design, a Handbook of Black Magic'',
Prentice Hall Prentice Hall is an American major educational publisher owned by Savvas Learning Company. Prentice Hall publishes print and digital content for the 6–12 and higher-education market. Prentice Hall distributes its technical titles through th ...
, 1973, * Roddy, Dennis, ''Satellite Communications'' third edition,
McGraw-Hill McGraw Hill is an American learning company and one of the "big three" educational publishers that provides customized educational content, software, and services for through . The company also provides reference and for the medical, busines ...
, 2001, {{ISBN, 0-07-137176-1 Network performance Temporal rates Information theory