Telecommunications in the context of Packet (information technology)

Infrastructure is the set of facilities and systems that serve a country, city, or other area, and encompasses the services and facilities necessary for its economy, households and firms to function. Infrastructure is composed of public and private physical structures such as roads, railways, bridges, airports, public transit systems, tunnels, water supply, sewers, electrical grids, and telecommunications (including Internet connectivity and broadband access). In general, infrastructure has been defined as "the physical components of interrelated systems providing commodities and services essential to enable, sustain, or enhance societal living conditions" and maintain the surrounding environment.

Especially in light of the massive societal transformations needed to mitigate and adapt to climate change, contemporary infrastructure conversations frequently focus on sustainable development and green infrastructure. Acknowledging this importance, the international community has created policy focused on sustainable infrastructure through the Sustainable Development Goals, especially Sustainable Development Goal 8 "Industry, Innovation and Infrastructure".

The Dallas–Fort Worth metroplex, officially designated Dallas–Fort Worth–Arlington by the U.S. Office of Management and Budget, is the most populous metropolitan statistical area in the U.S. state of Texas and the Southern U.S., encompassing 11 counties. Its historically dominant core cities are Dallas and Fort Worth. It is the economic and cultural hub of North Texas. Residents of the area also refer to it as DFW (the code for Dallas Fort Worth International Airport) or the Metroplex. The Dallas–Fort Worth–Arlington metropolitan statistical area's population was 7,637,387 according to the U.S. Census Bureau's 2020 census, making it the fourth-largest metropolitan area in the U.S. and the eleventh-largest in the Americas. In 2016, the Dallas–Fort Worth metroplex had the highest annual population growth in the United States. By 2023, the U.S. Census Bureau estimated that the Dallas-Fort Worth metropolitan area's population had increased to 8,100,037, with the highest numerical growth of any metropolitan area in the United States. By 2025, NCTCOG estimated that the Dallas-Fort Worth metropolitan area's population had increased to around 8,578,654 million residents, making the Dallas-Fort Worth metropolitan area around 1.42 million residents from becoming a megacity.

The metropolitan region's economy, also referred to as Silicon Prairie, is primarily based on banking, commerce, insurance, telecommunications, technology, energy, healthcare, medical research, transportation, manufacturing, and logistics. As of 2022, Dallas–Fort Worth is home to 23 Fortune 500 companies, the 4th-largest concentration of Fortune 500 companies in the United States behind New York City (62), Chicago (35), and Houston (24). In 2016, the metropolitan economy surpassed Houston, the second largest metro area in Texas, to become the fourth-largest in the U.S. The Dallas–Fort Worth metroplex boasted a GDP of just over $620.6 billion in 2020 (although both metropolitan regions have switched places multiple times since GDP began recording). If the Metroplex were a sovereign state, it would have the twentieth largest economy in the world as of 2019. In 2015, the conurbated metropolitan area would rank the ninth-largest economy if it were a U.S. state. In 2020, Dallas–Fort Worth was recognized as the 36th best metropolitan area for STEM professionals in the U.S.

Television (TV) is a telecommunication medium for transmitting moving images and sound. Additionally, the term can refer to a physical television set rather than the medium of transmission. Television is a mass medium for advertising, entertainment, news, and sports. The medium is capable of more than "radio broadcasting", which refers to an audio signal sent to radio receivers.

Television became available in crude experimental forms in the 1920s, but only after several years of further development was the new technology marketed to consumers. After World War II, an improved form of black-and-white television broadcasting became popular in the United Kingdom and the United States, and television sets became commonplace in homes, businesses, and institutions. During the 1950s, television was the primary medium for influencing public opinion. In the mid-1960s, color broadcasting was introduced in the U.S. and most other developed countries.

A communication channel refers either to a physical transmission medium such as a wire, or to a logical connection over a multiplexed medium such as a radio channel in telecommunications and computer networking. A channel is used for information transfer of, for example, a digital bit stream, from one or several senders to one or several receivers. A channel has a certain capacity for transmitting information, often measured by its bandwidth in Hz or its data rate in bits per second.

Communicating an information signal across distance requires some form of pathway or medium. These pathways, called communication channels, use two types of media: Transmission line-based telecommunications cable (e.g. twisted-pair, coaxial, and fiber-optic cable) and broadcast (e.g. microwave, satellite, radio, and infrared).

Information and communications technology (ICT) is an extensional term for information technology (IT) that stresses the role of unified communications and the integration of telecommunications (telephone lines and wireless signals) and computers, as well as necessary enterprise software, middleware, storage and audiovisual, that enable users to access, store, transmit, understand and manipulate information.

ICT is also used to refer to the convergence of audiovisuals and telephone networks with computer networks through a single cabling or link system. There are large economic incentives to merge the telephone networks with the computer network system using a single unified system of cabling, signal distribution, and management. ICT is an umbrella term that includes any communication device, encompassing radio, television, cell phones, computer and network hardware, satellite systems and so on, as well as the various services and appliances with them such as video conferencing and distance learning. ICT also includes analog technology, such as paper communication, and any mode that transmits communication.

The People's Republic of China has a developing mixed socialist market economy, incorporating industrial policies and strategic five-year plans. China has the world's second-largest economy by nominal GDP and since 2016 has been the world's largest economy when measured by purchasing power parity (PPP). China accounted for 19% of the global economy in 2022 in PPP terms, and around 18% in nominal terms in 2022. The economy consists of state-owned enterprises (SOEs) and mixed-ownership enterprises, as well as a large domestic private sector which contribute approximately 60% of the GDP, 80% of urban employment and 90% of new jobs.

China is the world's largest manufacturing industrial economy and exporter of goods. China is widely regarded as the "powerhouse of manufacturing", "the factory of the world" and the world's "manufacturing superpower". Its production exceeds that of the nine next largest manufacturers combined. However, exports as a percentage of GDP have steadily dropped to just around 20%, reflecting its decreasing importance to the Chinese economy. Nevertheless, it remains the largest trading nation in the world and plays a prominent role in international trade. Manufacturing has been transitioning toward high-tech industries such as electric vehicles, renewable energy, telecommunications and IT equipment, and services has also grown as a percentage of GDP. However, recent research indicates that China’s Total factor productivity (TFP) growth has slowed significantly. IMF estimates show that TFP growth declined from approximately 3.7% in the 2000s to around 1.9% during 2010–2019. Structural reforms and technological progress in manufacturing between 2010 and 2020 contributed only modestly to productivity gains. Additionally, a 2024–2025 IMF working paper finds that factor misallocation resulting from industrial and regulatory policies implemented since the early 2010s reduces China’s aggregate TFP by roughly 1.2% annually. IMF research suggests that while China’s state-led push for high-tech self-reliance since 2013 has supported rapid innovation, it has been accompanied by efficiency losses. Policy measures, including targeted state subsidies appear to favor politically connected firms, crowd out competition, and lead to overcapacity, undermining overall productivity. China is the world's largest high technology exporter. As of 2023, the country spends around 2.6% of GDP to advance research and development across various sectors of the economy. It is also the world's second-largest importer of goods. China is a net importer of services products.

A telecommunications company is a kind of electronic communications service provider, more precisely a telecommunications service provider (TSP), that provides telecommunications services such as telephony and data communications access. Many traditional solely telephone companies now function as internet service providers (ISPs), and the distinction between a telephone company and ISP has tended to disappear completely over time, as the current trend for supplier convergence in the industry develops. Additionally, with advances in technology development, other traditional separate industries such as cable television, Voice-over IP (VoIP), and satellite providers offer similar competing features as the telephone companies to both residential and businesses leading to further evolution of corporate identity have taken shape.

Due to the nature of capital expenditure involved in the past, most telecommunications companies were government-owned agencies or privately owned monopolies operated in most countries under close state regulation. But today there are many private players in most regions of the world, and even most of the government-owned companies have been opened up to competition in-line with World Trade Organization (WTO) policy agenda. Historically, these government agencies were often referred to, primarily in Europe, as PTTs (postal, telegraph and telephone services). Telecommunications companies are common carriers, and in the United States are also known as local exchange carriers. With the advent of mobile telephony, telecommunications companies now include wireless carriers, or mobile network operators and even satellite providers (Iridium).

A spacecraft is a vehicle that is designed to fly and operate in outer space. Spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, planetary exploration, and transportation of humans and cargo. All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket).

On a sub-orbital spaceflight, a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit. For orbital spaceflights, spacecraft enter closed orbits around the Earth or around other celestial bodies. Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit (space stations) only, whereas those used for robotic space missions operate either autonomously or telerobotically. Robotic spacecraft used to support scientific research are space probes. Robotic spacecraft that remain in orbit around a planetary body are artificial satellites. To date, only a handful of interstellar probes, such as Pioneer 10 and 11, Voyager 1 and 2, and New Horizons, are on trajectories that leave the Solar System.

Broadcasting is the distribution of audio and audiovisual content to dispersed audiences via an electronic mass communications medium, typically using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began with AM radio, which became popular around 1920 with the spread of vacuum tube radio transmitters and receivers. Before this, most implementations of electronic communication (early radio, telephone, and telegraph) were one-to-one, with the message intended for a single recipient. The term broadcasting evolved from its use as the agricultural method of sowing seeds in a field by casting them broadly about. It was later adopted for describing the widespread distribution of information by printed materials or by telegraph. Examples applying it to "one-to-many" radio transmissions of an individual station to multiple listeners appeared as early as 1898.

Over-the-air broadcasting is usually associated with radio and television, though more recently, both radio and television transmissions have begun to be distributed by cable (cable television). The receiving parties may include the general public or a relatively small subset; the point is that anyone with the appropriate receiving technology and equipment (e.g., a radio or television set) can receive the signal. The field of broadcasting includes both government-managed services such as public radio, community radio and public television, and private commercial radio and commercial television. The U.S. Code of Federal Regulations, title 47, part 97 defines broadcasting as "transmissions intended for reception by the general public, either direct or relayed". Private or two-way telecommunications transmissions do not qualify under this definition. For example, amateur ("ham") and citizens band (CB) radio operators are not allowed to broadcast. As defined, transmitting and broadcasting are not the same.

In telecommunications, broadband or high speed is the wide-bandwidth data transmission that uses signals at a wide spread of frequencies or several different simultaneous frequencies. It is used in fast Internet access where the transmission medium can be coaxial cable, optical fiber, wireless Internet (radio), twisted pair cable, or satellite.

Originally used to mean "using a wide-spread frequency" and for services that were analog at the lowest level, in the context of Internet access, "broadband" is now often used to mean any high-speed Internet access that is seemingly always "on" and is faster than dial-up access over traditional analog or ISDN PSTN services.

An entrepôt (English: /ˈɒntrəpoʊ/ ON-trə-poh; French: [ɑ̃tʁəpo] ) is a transshipment port, city, or trading post where merchandise may be imported, stored, or traded, usually to be exported again. Entrepôt also means 'warehouse' in modern French, and is derived from the Latin roots inter 'between' + positum 'position', literally 'that which is placed between'. Typically located on a crossroads, river, canal, or maritime trade route these trade hubs played a critical role in trade during the age of sail. Modern logistics, supply chain networks, and border controls have largely made entrepôts obsolete, or reduced them in number, but the term is still used to refer to duty-free ports or those with a high volume of re-export trade.

Railways, Container Ships, Air-Freight, and Telecommunications have created a world in which commodities and manufactured goods are shifted from one part of the globe to another in regular, controlled, and reliable streams; see Just-in-Time Manufacturing. Eliminating the factors which once made the entrepot phenomenon central to trade networks. But, as pointed out by the Dutch economist T.P. van der Kooy and has been more recently restated by P.W. Klein, before the Industrial Revolution the flow of goods from one part of the world to another, even one region of a country to another, was so irregular and unpredictable that there was no possibility of achieving any sort of steady distribution, any balancing of supply and demand, or any sort of price stability except by stockpiling great reserves of commodities in central storehouses; ie entrepots.

A telephone number is the address of a telecommunication endpoint, such as a telephone, in a telephone network, such as the public switched telephone network (PSTN). A telephone number typically consists of a sequence of digits, but historically letters were also used in connection with telephone exchange names.

Telephone numbers facilitate the switching and routing of calls using a system of destination code routing. Telephone numbers are entered or dialed by a calling party on the originating telephone set, which transmits the sequence of digits in the process of signaling to a telephone exchange. The exchange completes the call either to another locally connected subscriber or via the PSTN to the called party. Telephone numbers are assigned within the framework of a national or regional telephone numbering plan to subscribers by telephone service operators, which may be commercial entities, state-controlled administrations, or other telecommunication industry associations.

Queueing theory is the mathematical study of waiting lines, or queues. A queueing model is constructed so that queue lengths and waiting time can be predicted. Queueing theory is generally considered a branch of operations research because the results are often used when making business decisions about the resources needed to provide a service.

Queueing theory has its origins in research by Agner Krarup Erlang, who created models to describe the system of incoming calls at the Copenhagen Telephone Exchange Company. These ideas were seminal to the field of teletraffic engineering and have since seen applications in telecommunications, traffic engineering, computing, project management, and particularly industrial engineering, where they are applied in the design of factories, shops, offices, and hospitals.

Electronics is a scientific and engineering discipline that studies and applies the principles of physics to design, create, and operate devices that manipulate electrons and other electrically charged particles. It is a subfield of physics and electrical engineering which uses active devices such as transistors, diodes, and integrated circuits to control and amplify the flow of electric current and to convert it from one form to another, such as from alternating current (AC) to direct current (DC) or from analog signals to digital signals. Electronics is often contrasted with electrical power engineering, which focuses on generation, transmission, and distribution of electric power rather than signal processing or device level control.

Electronic devices have significantly influenced the development of many aspects of modern society, such as telecommunications, entertainment, education, health care, industry, and security. The main driving force behind the advancement of electronics is the semiconductor industry, which continually produces ever-more sophisticated electronic devices and circuits in response to global demand. The semiconductor industry is one of the global economy's largest and most profitable industries, with annual revenues exceeding $481 billion in 2018. The electronics industry also encompasses other branches that rely on electronic devices and systems, such as e-commerce, which generated over $29 trillion in online sales in 2017. Practical electronic systems commonly combine analog and digital techniques, using analog front ends with digital processing.

Digital signal processing (DSP) is the use of digital processing, such as by computers or more specialized digital signal processors, to perform a wide variety of signal processing operations. The digital signals processed in this manner are a sequence of numbers that represent samples of a continuous variable in a domain such as time, space, or frequency. In digital electronics, a digital signal is represented as a pulse train, which is typically generated by the switching of a transistor.

Digital signal processing and analog signal processing are subfields of signal processing. DSP applications include audio and speech processing, sonar, radar and other sensor array processing, spectral density estimation, statistical signal processing, digital image processing, data compression, video coding, audio coding, image compression, signal processing for telecommunications, control systems, biomedical engineering, and seismology, among others.

In telecommunications, transmission (sometimes abbreviated as "TX") is the process of sending or propagating an analog or digital signal via a medium that is wired, wireless, or fiber-optic.

In physics, acoustics, and telecommunications, a harmonic is a sinusoidal wave with a frequency that is a positive integer multiple of the fundamental frequency of a periodic signal. The fundamental frequency is also called the 1st harmonic; the other harmonics are known as higher harmonics. As all harmonics are periodic at the fundamental frequency, the sum of harmonics is also periodic at that frequency. The set of harmonics forms a harmonic series.

The term is employed in various disciplines, including music, physics, acoustics, electronic power transmission, radio technology, and other fields. For example, if the fundamental frequency is 50 Hz, a common AC power supply frequency, the frequencies of the first three higher harmonics are 100 Hz (2nd harmonic), 150 Hz (3rd harmonic), 200 Hz (4th harmonic) and any addition of waves with these frequencies is periodic at 50 Hz.

Information theory is the mathematical study of the quantification, storage, and communication of information. The field was established and formalized by Claude Shannon in the 1940s, though early contributions were made in the 1920s through the works of Harry Nyquist and Ralph Hartley. It is at the intersection of electronic engineering, mathematics, statistics, computer science, neurobiology, physics, and electrical engineering.

A key measure in information theory is entropy. Entropy quantifies the amount of uncertainty involved in the value of a random variable or the outcome of a random process. For example, identifying the outcome of a fair coin flip (which has two equally likely outcomes) provides less information (lower entropy, less uncertainty) than identifying the outcome from a roll of a die (which has six equally likely outcomes). Some other important measures in information theory are mutual information, channel capacity, error exponents, and relative entropy. Important sub-fields of information theory include source coding, algorithmic complexity theory, algorithmic information theory and information-theoretic security.

In computer science, computer engineering, and telecommunications, a network is a group of communicating computers and peripherals known as hosts, which communicate data to other hosts via communication protocols, as facilitated by networking hardware.

Within a computer network, hosts are identified by network addresses, which allow networking hardware to locate and identify hosts. Hosts may also have hostnames, memorable labels for the host nodes, which can be mapped to a network address using a hosts file or a name server such as Domain Name Service. The physical medium that supports information exchange includes wired media like copper cables, optical fibers, and wireless radio-frequency media. The arrangement of hosts and hardware within a network architecture is known as the network topology.