Broadcast - это

1) радиовещательный Mr Thornton's broadcast talks on exotic music are widely known. ? Радиопрограммы мистера Торнтона о необычных направлениях в музыке широко известны. broadcast appeal

broadcast — ?. broadcast UK US /?br??dk??st/ US  /?br??d?k?st/ verb [I or T] (broadcast, US also broadcasted, broadcast, US also broadcasted) COMMUNICATIONS > to send out a programme on television or radio, or over the internet: »The company s final quarter… … Financial and business terms

Broadcast — Saltar a navegacion, busqueda Broadcast puede designar: Broadcast (informatica), transmision de un paquete que sera recibido por todos los dispositivos en una red. El Dominio de difusion, mas conocido como dominio broadcast en ingles, un segmento … Wikipedia Espanol

Broadcast — Broadcast  передача (вещание) сигналов, например аудио/видео: В Викисловаре есть статья «broadcast» Broadcasting  маршрутизация … Википедия

broadcast — broadcast; ra·dio·broadcast; re·broadcast; … English syllables

broadcast — [n] information on electronic media advertisement, air time, announcement, newscast, performance, program, publication, radiocast, show, simulcast, telecast, transmission; concepts 274,293 broadcast [v1] put forth on electronic media air,… … New thesaurus

broadcast — > VERB (past broadcast; past part. broadcast or broadcasted) 1) transmit by radio or television. 2) tell to many people. 3) scatter (seeds) rather than placing in drills or rows. > NOUN ? a radio or television programme or transmi … English terms dictionary

broadcast — [brod?kast?, brod?kast?] vt. broadcast or broadcasted, broadcasting 1. to scatter (seed) over a broad area rather than sow in drills 2. to spread (information, gossip, etc.) widely 3. to transmit, as to a large audience, by radio or television vi … English World dictionary

Broadcast — (o en castellano difusiones ). se producen cuando una fuente envia datos a todos los dispositivos de una red. En la tecnologia Ethernet el broadcast se realiza enviando tramas con direccion MAC de destino FF.FF.FF.FF.FF.FF. En el protocolo IP se … Enciclopedia Universal

broadcast — verb, by analogy with cast, is unchanged in its past form and past participle: The programme will be broadcast on Saturdays … Modern English usage

Broadcast — Broad cast. a. 1. Cast or dispersed in all directions, as seed from the hand in sowing; widely diffused. [1913 Webster] 2. Scattering in all directions (as a method of sowing); opposed to planting in hills, or rows. [1913 Webster] … The Collaborative International Dictionary of English

Broadcast — Broad cast. adv. So as to scatter or be scattered in all directions; so as to spread widely, as seed from the hand in sowing, or news from the press. [1913 Webster] … The Collaborative International Dictionary of English

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Передача Unicast, Broadcast и Multicast трафика

Существует три основных метода передачи трафика в IP-сетях, это - Unicast, Broadcast и Multicast.

Понимание разницы между этими методами является очень важным для понимания преимуществ IP-телевидения и для практической организации трансляции видео в IP-сети.

Каждый из этих трех методов передачи использует различные типы назначения IP-адресов в соответствии с их задачами и имеется большая разница в степени их влияния на объем потребляемого трафика.

Unicast трафик (одноцелевая передача пакетов) используется прежде всего для сервисов «персонального» характера. Каждый абонент может запросить персональный видео-контент в произвольное, удобное ему время.

Unicast трафик направляется из одного источника к одному IP-адресу назначения. Этот адрес принадлежит в сети только одному единственному компьютеру или абонентскому STB как показано на рисунке ниже.

Число абонентов, которые могут получать unicast трафик одновременно, ограничено доступной в магистральной части сети шириной потока (скоростью потока). Для случая Gigabit Ethernet сети теоретическая максимальная ширина потока данных может приближаться к 1 Гб/сек за вычетом полосы, необходимой для передачи служебной информации и технологических запасов оборудования. Предположим, что в магистральной части сети мы можем для примера выделить не более половины полосы для сервисов, которым требуется unicast трафик. Легко подсчитать для случая 5Мб/сек на телевизионный канал MPEG2, что число одновременно получающих unicast трафик абонентов не может превышать 100.

Broadcast трафик (широковещательная передача пакетов) использует специальный IP-адрес, чтобы посылать один и тот же поток данных ко всем абонентам данной IP-сети. Например, такой IP-адрес может оканчиваться на 255, например 192.0.2.255, или иметь 255 во всех четырех полях (255.255.255.255).

Важно знать, что broadcastтрафик принимается всеми включенными компьютерами (или STB) в сети независимо от желания пользователя. По этой причине этот вид передачи используется в основном для служебной информации сетевого уровня или для передачи другой исключительно узкополосной информации. Разумеется, для передачи видео-данных broadcast трафик не используется. Пример передачи broadcastтрафика показан на рисунке ниже.

Multicast трафик (групповая передача пакетов) используется для передачи потокового видео, когда необходимо доставить видео-контент неограниченному числу абонентов, не перегружая сеть. Это наиболее часто используемый тип передачи данных в IPTV сетях, когда одну и ту же программу смотрят большое число абонентов.

Multicast трафик использует специальный класс IP-адресов назначения, например адреса в диапазоне 224.0.0.0 …. 239.255.255.255. Это могут быть IP-адреса класса D.

В отличие от unicast трафика, multicast адреса не могут быть назначены индивидуальным компьютерам (или STB). Когда данные посылаются по одному из multicast IP-адресов, потенциальный приемник данных может принять решение принимать или не принимать их, то есть будет абонент смотреть этот канал или нет. Такой способ передачи означает, что головное оборудование IPTV оператора будет передавать один единственный поток данных по многим адресам назначения. В отличие от случая broadcast передачи, за абонентом остается выбор - принимать данные или нет.

Важно знать, что для реализации multicast передачи в IP-сети должны быть маршрутизаторы, поддерживающие multicast. Маршрутизаторы используют протокол IGMP для отслеживания текущего состояния групп рассылки (а именно, членство в той или иной группе того или иного конечного узла сети).

Основные правила работы протокола IGMP следующие:

- конечный узел сети посылает пакет IGMP типа report для обеспечения запуска процесса подключения к группе рассылки;

- узел не посылает никаких дополнительных пакетов при отключении от группы рассылки;

- маршрутизатор m ulticast через определенные временные интервалы посылает в сеть запросы IGMP. Эти запросы позволяют определить текущее состояние групп рассылки;

- узел посылает ответный пакет IGMP для каждой группы рассылки до тех пор, пока имеется хотя бы один клиент данной группы.

Загрузка магистральной части сети multicast трафиком зависит только от числа транслируемых в сети каналов. В ситуации с Gigabit Ethernet сетью, предположив, что половину магистрального трафика мы можем выделить под multicast передачу, мы получаем около 100 телевизионных MPEG-2 каналов, каждый имеющий скорость потока данных 5 Мб/сек.

Разумеется, в IPTV сети присутствуют одновременно все 3 вида трафика broadcast, multicast и unicast. Оператор, планируя оптимальную величину пропускной способности сети, должен учитывать разный механизм влияния разных технологий IP- адресации на объем трафика. Например, оператор должен ясно представлять себе, что предоставление услуги «видео на заказ» большому числу абонентов требует очень высокой пропускной способности магистральной сети. Одним из решений этой проблемы является децентрализация в сети видео-серверов. В этом случае центральный видео-сервер заменяется на несколько локальных серверов, разнесенных между собой и приближенных к периферийным сегментам многоуровневой иерархической архитектуры IP-сети.

Блокировки за broadcast и multicast - Скорая Компьютерная Помощь

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Что такое?

Ну что ж, начасть стоит с того, что же представляет из себя броадкаст и мультикаст трафик и почему его так боятся провайдеры?

Флуд (англ. flood) -атака, связанная с большим количеством обычно бессмысленных или сформированных в неправильном формате запросов к компьютерной системе или сетевому оборудованию, имеющая своей целью или приведшая к отказу в работе системы из-за исчерпания ресурсов системы -процессора, памяти либо каналов связи. Если атака (обычно флуд) производится одновременно с большого количества IP-адресов, то в этом случае она называется распределённой атакой на отказ в обслуживании (DDoS).

Что такое широковещательный (broadcast) трафик? Это пакеты информации, которые назначены для получения всеми компьютерами сети. Такие пакеты в основном предназначены для получения адреса какого-либо компьютера в сети (arp пакеты) или адреса компьютера, на котором работает какой-либо сетевой сервис (ip broadcast). В нормальном режиме работы одна машина в сети рассылает порядка 10-20 таких пакетов в минуту. Если вы наблюдаете большое значение Milticast\Broadcast RX в столбце Frames/sec - это и есть флуд. (команда sh packet ports) Если идут прыжки >10 frames per sec - у клиента явно проблемы

Что такое широковещательный (multicast) трафик? Это многоадресная рассылка, в широком смысле слова – связь между ОДНИМ отправителем и несколькими получателями. В отличие от BROADCAST сообщений, посылаемым всем адресатам сети, MULTICAST сообщения отправляются определенной подгруппе сетевых адресов, которая представляет собой несуществующий MAC-адрес определенный в данном протоколе многоадресной рассылки. Суть многоадресной рассылки (MULTICAST) в том, что она позволяет нескольким получателям принимать сообщения БЕЗ передачи сообщений каждому хосту BROADCAST домена. MULTICAST подобна почтовой рассылке: пользователь или приложение ПОДПИСЫВАЮТСЯ на определенную группу многоадресной рассылки. Если хост не подписан на группу, он не обрабатывает пакеты, ей адресованные. В BROADCAST коммуникации имеется глобальный адрес (255.255.255.255), на который отвечают все узлы. Многоадресная рассылка применяет адреса, на которые отвечают лишь некоторые узлы (которых подписали). Область MULTICAST охватывает адреса 224.0.0.0 – 239.255.255.255. Управляется протоколами IGMP (Internet Group Management Protocol – есть несколько версий) и CGMP (CISCO Group Management Protocol – работает только на оборудовании CISCO).

Зачем нужна фильтрация широковещательного трафика? Как уже было сказано, broadcast и multicast пакеты получают все компьютеры в сети и соответственно на каждый пакет тратиться время на коммутаторах чтобы его переслать и на каждом компьютере на обработку этого пакета. При нормальном режиме это не вызывает каких либо проблем, но в последнее время появились вирусы, т.н. черви (worms). которые после заражения машины начинают искать другие хосты в сети, которые можно заразить, и делают это, рассылая broadcast или multicast пакеты со скоростью до 10000 в минуту. Несколько таких зараженных машин в сети достаточно, чтобы существенно понизить общую пропускную способность.

Лимит широковещательного трафика по Калуге - 10 фреймов в секунду, за превышение лимита порт на свитче сначала кладётся на сутки, потом перманентно (разблокировка происходит только после звонка в компанию).

Итак. Что же может быть причиной генерации широковещательного трафика?

1. Основная и самая частая причина флуда - вирусы.

2. В windows vista причиной multicast шторма может быть активный IPv6 протокол. Его необходимо отключать.

3. Кроме того, причиной флуда могут служить компьютерные игры :

-Command & Conquer 3

-Dungeon Siege

-Armed Assault

-Left for Dead (Решение проблемы находится на форуме homenet.corbina.net в разделе: "Домашний интернет Corbina telecom - форумы > Игровые ресурсы. Кураторы подраздела: Warhead и Barmaley > Online игры > Игровой Портал >Новинки")

1. NetBIOS-трафик. Основной источник флуда в сети и инициатор лавинных ARP-запросов. По поводу отключения см. здесь: http://virusinfo.info/showthread.php?t=4243

2. Сервисы SSDP (UPnP) и IGMP иногда анонсируют себя в сети. Клиенты этих сервисов также применяют multicast для поиска серверов. Периодичности не заметил, скорее всего работают по запросу приложений верхних уровней, например, клиентов с поддержкой UPnP.

3. P2P-клиенты могут искать пиров в локальной сети при определённых обстоятельствах. Например, uTorrent при отключенном VPN каждые 5 минут высылает пачкой N запросов, где N - число запущенных торрентов: BT-SEARCH * HTTP/1.1 Host: 239.192.152.143:6771 Вызывает Multicast storm на порту.

4. IPX. Иногда встречается в сети. Протокол имеет репутацию засирателя локальных сетей.

5. Сервис Bonjour, устанавливаемый с некоторыми продуктами Adobe. Стреляет мультикастами на 224.0.0.251 при инициализации интерфейсов. Судя по отзывам пользователей, вызывает блокировки за Multicast flood.

6. Одноранговые сетевые чаты и файлообменники типа Vypress Chat. Работают на UDP поверх multicast'а или broadcast'а.

7. Некоторые кривые сетевые карты и их драйверы (отличный пример - USB сетевая D-link DUB-E100 )

Меня заблокировали! Что делать?

Симптомы при блокировке порта очень простые: ОС пишет "сетевой кабель не подключен", т.е. происходит тоже самое что и при обрыве кабеля. Узнать в чем же собственно проблема можно только позвонив по 555-000, где оператор сможет сразу определить источник неисправности (ну а если не сможет - определит инженер тех. поддержки). Узнав что вы заблокированы - не надо беситься и истекать слюнями, никому ничего доказать не удастся (см. договор: (Условия предоставления услуги) п.1.2 :

- действия, направленные на получение несанкционированного доступа или нарушение нормального функционирования сетей передачи данных, телематических служб, телефонной сети, их элементов, а так же компьютеров, другого оборудования или программного обеспечения, не принадлежащего Заказчику

Broadcasting - New World Encyclopedia

The term broadcast was coined by early radio engineers from the mid-western United States to distinguish electronic transmissions that are intended for general public reception, as distinguished from private signals that are directed to specific receivers. Broadcasting forms a very large segment of the mass media. Television and radio programs are distributed through radio broadcasting or cable, often both simultaneously. By coding signals and having decoding equipment in homes, cable also enables subscription-based channels and pay-per-view services.

A broadcasting organization may broadcast several programs at the same time, through several channels (frequencies); for example, the BBC broadcasts BBC One and BBC Two. On the other hand, two or more organizations may share a channel and each use it during a fixed part of the day. Digital radio and digital television may also transmit multiplexed programming, with several channels compressed into one ensemble.

When broadcasting is done via the Internet. the term "webcasting" is often used.

Defining exactly when broadcasting first began is difficult. Very early radio transmissions only carried the dots and dashes of wireless telegraphy. Broadcasting in its familiar sense, sending signals to inform and entertain large numbers of people, began in the early twentieth century. Countries in which notable advances were made in the early decades of the twentieth century include the United States. Britain. Germany. and Sri Lanka .

One of the first signals of significant power that carried voice and music was accomplished, in 1906, by Reginald Fessenden when he made a Christmas Eve broadcast to ships at sea from Massachusetts. He played "O Holy Night" on his violin and read passages from the Bible. However, his financial backers lost interest in the project, leaving others to take the next steps. Early on, the concept of broadcasting was new and unusual—with telegraphs, communication had been one-to-one, not one-to-many. Sending out one-way messages to multiple receivers did not appear to have much practical use.

Charles Herrold of California sent out broadcasts as early as April 1909 from his Herrold School electronics institute in downtown San Jose, using the identification San Jose Calling, and then a variety of different "call signs" as the Department of Commerce first began to regulate radio. The son of a farmer who patented a seed spreader, Herrold coined the terms "broadcasting" and "narrowcasting," based on the ideas of spreading crop seed far and wide, rather than only in rows. While Herrold never claimed the invention of radio itself, he did claim the invention of broadcasting to a wide audience, through the use of antennas designed to radiate signals in all directions.

By 1912, the United States government began requiring radio operators to obtain licenses to send out signals. Herrold received licenses for 6XF and 6XE (a mobile transmitter) and had been on the air daily for nearly a decade when World War I interrupted operations. A few organizations were allowed to keep working on radio during the war. The Westinghouse Electric Corporation was the most well-known of these. Frank Conrad, a Westinghouse engineer, had been making transmissions from 8XK since 1916, that included music programming.

Following the war, Herrold and other radio pioneers across the country resumed transmissions. The early stations gained new call signs. Conrad's 8XK became KDKA in 1920. Herrold received a license for KQW in 1921, later to become KCBS a CBS -owned station in San Francisco.

The National Broadcasting Company (NBC) began regular broadcasting in 1926, with telephone links between New York City and other eastern cities. NBC became the dominant radio network, splitting into Red and Blue networks. The Columbia Broadcasting System (CBS) began in 1927, under the guidance of William S. Paley. Several independent stations formed the Mutual Broadcasting System to exchange syndicated programming.

A Federal Communications Commission decision in 1939 required NBC to divest itself of its "Blue Network." That decision was sustained by the Supreme Court in a 1943 decision, National Broadcasting Co. v. United States, which established the framework that the "scarcity" of radio-frequency meant that broadcasting was subject to greater regulation than other media. This Blue Network became the American Broadcasting Company (ABC). Around 1946, ABC, NBC, and CBS began regular television broadcasts. Another network, the DuMont Television Network, founded earlier, was disbanded in 1956.

The first experimental broadcasts, from Marconi's factory in Chelmsford, England. began in 1920. Two years later, a consortium of radio manufacturers formed the British Broadcasting Company, later becoming the British Broadcasting Corporation (BBC), a non-commercial organization.

Lord John Reith took a formative role in developing the BBC, especially in radio. Working as its first general manager, he promoted the philosophy of "public service broadcasting," firmly grounded in the moral benefits of education and of uplifting entertainment, eschewing commercial influence, and maintaining a maximum of independence from political control.

Commercial stations such as Radio Normandie and Radio Luxembourg broadcast into the UK from European countries, providing a very popular alternative to the rather austere BBC. These stations were closed during World War II. and only Radio Luxembourg returned afterward.

BBC television broadcasts in Britain began on November 2, 1936, and have continued with the exception of wartime conditions from 1939 to 1945.

Before the Nazi assumption of power in 1933, German radio broadcasting was supervised by the Post Office. A listening fee for each receiver paid most subsidies.

Immediately following Hitler's assumption of power, Joseph Goebbels became head of the Ministry for Propaganda and Public Enlightenment. Non-Nazis were removed from broadcasting and editorial positions. Jews were fired from all positions. German broadcasting began to decline in popularity as the theme of Kampfzeit was continually played. Germany was easily served by a number of European medium wave stations, including the BBC and domestic stations in France. Denmark. Sweden. and Poland. It became illegal for Germans, with the exception of foreign correspondents and key officials, to listen to foreign broadcasts.

During the war, German stations broadcast not only war propaganda and entertainment for German forces dispersed throughout Europe and the Atlantic. but also provided air raid alerts.

Germany experimented with television broadcasting before the Second World War. German propaganda claimed their system was superior to the British scanning system, but this was disputed by persons who saw the broadcasts.

Sri Lanka has the oldest radio station in Asia. The station, originally known as Radio Ceylon, developed into one of the finest broadcasting institutions in the world. It is now known as the Sri Lanka Broadcasting Corporation.

Sri Lanka created broadcasting history in Asia in 1923, when broadcasting was started in Ceylon by the Telegraph Department on an experimental footing, just three years after the inauguration of broadcasting in Europe. Gramophone music was broadcast from a tiny room in the Central Telegraph Office with the aid of a small transmitter built by the Telegraph Department engineers from the radio equipment of a captured German submarine .

Edward Harper, dubbed "the father of broadcasting in Ceylon," launched the first experimental broadcast as well as founding the Ceylon Wireless Club together with British and Ceylonese radio enthusiasts. This broadcasting experiment was a huge success and barely three years later, on December 16, 1925, a regular broadcasting service was instituted.

In the 1950s, television began to replace radio as the chief source of revenue for broadcasting networks. Although many radio programs continued through this decade, including Gunsmoke and The Guiding Light, by 1960, radio networks had ceased producing entertainment programs.

As radio stopped producing formal 15-minute to hourly programs, a new format developed—Top 40. "Top 40" was based on a continuous rotation of short pop songs presented by a "disc jockey." Top 40 playlists were theoretically based on record sales; however, record companies began to bribe disc jockeys to play selected artists.

Shortwave broadcasting played an important part in fighting the Cold War with Voice of America and the BBC World Service, augmented with Radio Free Europe and Radio Liberty transmitting through the "Iron Curtain." Radio Moscow and others broadcasted back, jamming (transmitting to cause intentional interference) the voices of the West.

In the 1950s, American television networks introduced broadcasts in color. The Federal Communications Commission approved the world's first monochrome-compatible color television standard in December 1953. The first network colorcast followed on January 1, 1954, with NBC transmitting the annual Tournament of Roses Parade in Pasadena, California. to over 20 stations across the country.

In 1952, an educational television network, National Educational Television (NET), predecessor to PBS. was founded.

The growth of FM (frequency modulated) radio in the 1970s changed the habits of younger listeners. Many stations such as WNEW-FM in New York City began to play whole sides of record albums, as opposed to the "Top 40" model of two decades earlier.

AM (amplitude modulated) radio declined throughout the 1970s and 1980s, due to various reasons including the lower cost of FM receivers, narrow AM audio bandwidth, poor sound in the AM section of automobile receivers, and increased radio noise in homes caused by fluorescent lighting and the introduction of electronic devices. AM radio's decline flattened out in the mid-1990s due to the introduction of niche formats and over-commercialization of many FM stations.

The 2000s saw the introduction of digital radio and direct broadcasting by satellite (DBS). Digital radios began to be sold in the United Kingdom in 1998.

Digital radio services, except in the United States, were allocated a new frequency band in the range of 1,400 MHz. In the United States, this band was deemed to be vital to national defense, so an alternate band in the range of 2,300 MHz was introduced for satellite broadcasting. American companies introduced DBS systems, which are funded by direct subscription, like cable television. European and Australian stations also began digital broadcasting (Digital Audio Broadcast).

A broadcast may be distributed through several physical means. If coming directly from the studio at a single broadcast station, it is simply sent through the air chain to the transmitter. Programming may also come through a communications satellite. played either live or recorded for later transmission. Networks of stations may simulcast the same programming at the same time.

Distribution to stations or networks may also be through physical media, such as analog or digital videotape, CD, DVD, or other format. Usually these are included in another broadcast, such as when electronic news gathering returns a story to the station for inclusion on a news program.

The final leg of broadcast distribution is how the signal reaches the listener or viewer. It may come over the air as with a radio station or TV station to an antenna and receiver, or may come through cable TV or cable radio. The Internet may also bring either radio or TV to the recipient, especially with multicasting, allowing the signal and bandwidth to be shared.

The term "broadcast network" is often used to distinguish networks that broadcast an over-the-air television signal that can be received using a television antenna from so-called networks that are broadcast only via cable or satellite television. The term "broadcast television" can refer to the programming of such networks. In the U.S. examples of broadcast networks that transmit programming to member stations are ABC. CBS. NBC. and Fox .

Broadcasting may be recorded or live. The former allows correcting errors, and removing superfluous or undesired material, rearranging it, applying slow-motion and repetitions, and other techniques to enhance the program. However, some live events like sports telecasts may include some of the features of recorded shows, such as slow-motion clips of important features of the game, in between the live action.

American radio network broadcasters habitually forbade prerecorded broadcasts in the 1930s and 1940s, requiring radio programs played for the eastern and central time zones to be repeated three hours later for the Pacific time zone. This restriction was dropped for special occasions, as in the case of the German dirigible airship Hindenburg at Lakehurst, New Jersey in 1937. During World War II. prerecorded broadcasts from war correspondents were allowed on U.S. radio. In addition, American radio programs were recorded for playback by Armed Forces Radio stations around the world.

A disadvantage of recording is that the public may know the outcome of an event from another source before the recording is broadcast. An advantage of recording is that it prevents announcers from deviating from an officially approved script, as occurred with propaganda broadcasts from Germany in the 1940s and with Radio Moscow in the 1980s.

Many events are advertised as being live, although they are often "recorded live." This is particularly true of performances of musical artists on radio when they visit for an in-studio concert performance. This intentional blurring of the distinction between live and recorded media is viewed with chagrin among many music lovers. Similar situations may appear in television, when a show is recorded in front of a live studio audience, and perhaps broadcast a few hours later (such as late-night variety shows).

There are several dominant business models of broadcasting. Each differs in the method by which stations are funded:

• Individually donated time and energy
• Direct government payments or operation
• Indirect government payments, such as radio and television licenses
• Grants from foundations or business entities
• Selling advertising or sponsorship
• Public subscription or membership
• Fees charged to all owners of TV sets or radios, regardless of whether they intend to receive that program or not

Broadcasters may rely on a combination of these business models. For example, National Public Radio (NPR), a non-commercial network within the United States. receives grants from the Corporation for Public Broadcasting, (which in turn receives funding from the U.S. government), by public membership, and by selling "extended credits" to corporations. Member NPR stations regularly fundraise over-the-air to augment subsidies.

Aside from usually being profit-making, broadcasting is a tremendous medium for art. Those who work with the spoken word, film, or in music. are able to utilize broadcasting to convey their work to more people simultaneously than could ever fit in an assembly or concert hall. Broadcasting also allows for art to spread over vast expanses of terrain quicker than moving in person.

The new media of television and radio led to the creation of entirely new methods to best suit them. Radio personalities develop personas unique unto themselves that allow for the best connection with their audience. [1] Television has led to a spur of technological and art advances as producers, actors, and directors had the freedom of working in a shorter format than full length feature films.

Television allows for the direct control of images and sounds to be seen by the audience, creating an entirely engrossing experience. [1] This type of experience, although without actual physical presence, engenders a greater sense of intimacy between speaker or performer and audience than a public stage.

Though broadcasting represents great opportunity, perfecting the new media has been difficult. Modern audiences looking back on historical performances can see the advances made in stories, pacing, direction, and performance.

Broadcasting has somewhat removed the communal aspect of performances as people watch or listen to broadcasts in their homes rather than in public places such as movie theaters or concert halls. This may contribute to the weakening of social ties, as it takes away another opportunity for socializing. The importance of this removal of social ties was made clear in the work of Emile Durkheim. who wrote of the phenomenon known as anomie. which describes a state of normlessness brought about by lack of human contact and belonging.

The anonymous nature of the broadcast market now, however, allows for the refinement and expression of exact tastes, as audience members do not have to defend or publicize their viewing or listening to any type of program as it is in the privacy of their home.

While the viewer may remain anonymous, the content of the material that enters homes has significant impact on human lives. Although there are constraints on the information allowed to be broadcast, many of the scenes in television programs showing news, current affairs, or interviews with celebrities, may shock viewers and change their outlook on life, either of those within their own country or in distant parts of the world. Disasters, such as the Indian Ocean tsunami of 2004, which took over 200,000 lives, and Hurricane Katrina, which devastated New Orleans in 2005, were reported instantly around the world. This led to greater awareness of the victims' suffering and outpourings of disaster relief efforts. The phenomenon of "embedded reporters" during the 2003 invasion of Iraq allowed live scenes of military action to be broadcast continuously on television. The broadcast images shown on television channels such as CNN. which included the bodies of slain Iraqis, literally brought home the reality of war to many households. Such experiences put a face on the otherwise anonymous victims of natural and man-made disasters.

There are a number of standards to which broadcasters around the world must adhere. In America, the body that decides these standards is the Federal Communications Commission (FCC), which in part lays out standards of decency. The FCC defines the amount of public service programming each broadcaster must provide, rules of ownership, and what is appropriate for public viewing at certain hours. The FCC levies fines against broadcasters that air material considered to be obscene. The FCC has been criticized as too strict in light of rulings over the broadcast of the film Saving Private Ryan [2] and the Janet Jackson wardrobe "mishap" during the 2004 Super Bowl. [3]

There also exist a number of private watchdog groups that monitor and critique decency and accuracy in radio, film, and television. These groups include Fairness & Accuracy In Media (FAIR) and Accuracy in Media (AIM).

^ 1.0 1.1 Encyclopedia Britannica, The Art of Radio. Retrieved December 2, 2006. ^ Washington Post, Saving Private Ryan: A New Casualty of the Indecency War. Retrieved December 4, 2006 ^ CNN, Apologetic Jackson says "costume reveal" went awry. Retrieved December 4, 2006.

All links retrieved March 7, 2013.

• Arbitron – Offers dozens of free studies on American radio listening habits of interest to radio stations and listeners alike, as well as free access to basic station information.
• Broadcasting Timeline
• DXing.info – News and info on international radio broadcasting
• Radio Locator – A service that helps find out information, such as format, power, coverage, etc. about any American radio station
• TVZ – TV Broadcast Services information and directory.
• TV Newsday – Current news about the U.S. TV broadcasting industry

Broadcast Terms of Service Agreement

Unless agreed otherwise in writing by Skype, any use of the Skype Software in a Program (as defined below) for Broadcast (as defined below) shall be subject to these Broadcast TOS.

If You want to use the Skype Software in a Program for Broadcast, You must agree to these Broadcast TOS.

Unless agreed otherwise in writing by Skype, if You do not agree to these Broadcast TOS You may not use the Skype Software in a Program for Broadcast.

When using the Skype Software in any Program for Broadcast You agree to comply with any applicable terms of the Skype Broadcast Guidelines (as may be updated from time to time) and the following additional requirements, except where prohibited by law:

2 .1 Audio Programs. With respect to any Program where there is no visual image being Broadcast, the following requirements apply:

(a) For any Program where use of the Skype Software will be fifteen (15) minutes or less in duration, You shall transmit an identification announcement at the beginning and end of such use, as described in the Skype Broadcast Guidelines ;

(b) For any Program where the use of the Skype Software will be for more than fifteen (15) minutes in duration, You shall transmit an identification announcement at the beginning and end of such use and over the course of the Program in no less than fifteen (15) minute intervals, as described in the Skype Broadcast Guidelines ; and

(c) If You wish to include in any Program a sound to represent a particular Skype-calling feature or action (for example, but without limitation, a “call answer” sound for when a call is accepted or a “hang-up” sound for when a call is terminated) You shall use only the Skype specific sounds provided by Skype and You shall further comply with the requirements relating to the use of Skype sounds set out in the Skype Broadcast Guidelines. To request a Skype sound, contact: media@skype.net

2 .2 Audiovisual Programs. With respect to any audiovisual Program (i.e. where a visual image is Broadcast with an accompanying audio signal) in which You use the Skype Software or include a video depiction of the Skype Software, the following requirements apply:

(a) You shall retrieve the Skype logo in scalable vector file format from here ;

(b) In any Program that uses or includes a visual depiction of the Skype Software, You shall place the Skype logo so that during such use it shall appear, scaled proportionately and to a reasonable size so that it is clearly legible and Your use of the Skype logo must comply with all requirements set out in the Skype Broadcast Guidelines ;

(c) If You want to mimic a specific device in your Program, You shall only use the Skype User Interface appropriate to the device as shown in the Skype Broadcast Guidelines. If you require Skype User Interface templates and assets please request them from: media@skype.net and

(d) If You wish to include in any Program a sound to represent a particular Skype-calling feature or action (for example, but without limitation, a “call answer” sound for when a call is accepted or a “call hang-up” sound for when a call is terminated) You shall use only the Skype specific sounds provided to You by Skype and You shall further comply with the requirements relating to the use of Skype sounds set it in the Skype Broadcast Guidelines. To request a Skype sound, contact: media@skype.net

3 .1 Definitions

3.1.1 “ Broadcast ” means to transmit simultaneously to the general public through any now known and unknown media and formats, including, without limitation, a data communications network, the Internet, electronic mail system, television, radio or satellite system, point to multipoint transmission over a wired, wireless or fiber network; and for purposes of these Broadcast TOS shall also include narrowcasting and multicasting.

3.1.2 “ Program ” means a live or pre-recorded audio or visual performance.

3 .2 You represent and warrant that You are authorized to agree to and comply with the terms and conditions of these Broadcast TOS. You are responsible for clearing all rights and paying all licensing fees and other costs and expenses arising from the Program and the Broadcast. In no event shall Skype be responsible for any costs or expenses incurred in connection with the Program or the Broadcast.

3 .3 You shall be responsible, at Your expense, for compliance with all applicable laws pertaining to the Program and the Broadcast. You agree to indemnify, defend and hold Skype, its Affiliates and the Skype staff harmless from and against any and all losses, costs, liabilities, damages, and expenses (including reasonable legal fees and other expenses incidental thereto) of every kind, nature and description, arising from: (i) the Broadcasts and the Programs; (ii) any misrepresentation or breach of any warranty of Yours contained in these Broadcast TOS; or (iii) any breach of any covenant, agreement, or obligation of Yours contained in these Broadcast TOS.

3 .4 You will take care to observe and exercise reasonable diligence to ensure that the Programs, Broadcast and/or the Skype Software will not: (i) be used as a medium for attack on any individual, organization, faith, denomination or sect; (ii) contain any announcements or promotions prohibited by law; (iii) be used to make false or unwarranted claims for any product or service; (iv) contain any content or announcements that are slanderous, obscene, profane, indecent, vulgar, repulsive or offensive, either in theme or in treatment; (v) contain any testimonials which cannot be authenticated; (vi) contain any descriptions or references to matters which are not considered acceptable topics of discussion in social groups (e.g. profanity, obscenity); or (vii) be used in connection with any advertising matter or announcement which may, in the opinion of Skype, be injurious or prejudicial to the interests of the public, Skype, or honest advertising and reputable business in general.

3 .5 The rights granted to You hereunder are non-exclusive and revocable. You shall not acquire any right, title or interest in or to any Skype logos, trademarks or other indicia of origin (collectively, the “Skype Brand”) and You hereby acknowledge that as between You and Skype, that Skype is the exclusive owner of all right, title and interest in and to the Skype Brand. Your use of the Skype Brand hereunder shall inure to the benefit of Skype. Skype reserves the right to instruct You on the use of the Skype Brand and how the Skype Brand is presented during the course of the Programs. Skype may also instruct You to cease use of the Skype Brand in the event such usage is, in Skype’s sole and absolute discretion, unacceptable to Skype. In the event You are so instructed to cease use of the Skype Brand, You shall immediately do so (and if such instruction relates to a particular Program, You shall no longer be permitted to Broadcast or license the Broadcast of such Program).

3 .6 Skype reserves the right to modify these Broadcast TOS at any time. Your continued usage of the Skype Software as authorised herein shall constitute Your acceptance to be bound by the terms and conditions of the revised Broadcast TOS. Skype will not be liable in relation to any damage caused by the modification of these Broadcast TOS and/or the termination thereof.

3 .7 YOU EXPRESSLY ACKNOWLEDGE THAT YOU HAVE READ THESE BROADCAST TOS AND UNDERSTAND THE RIGHTS, OBLIGATIONS, TERMS AND CONDITIONS SET FORTH HEREIN. BY USING THE SKYPE SOFTWARE IN THE MANNER AUTHORISED HEREIN, YOU EXPRESSLY CONSENT TO BE BOUND BY THESE TERMS AND CONDITIONS AND GRANT TO SKYPE THE RIGHTS SET FORTH HEREIN.

© Skype – Last revised: 13 August 2014