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Voice Over Internet Protocol
Voice over Internet Protocol (VoIP), also called IP telephony, is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet. The terms Internet telephony, broadband telephony, and broadband phone service specifically refer to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the Internet, rather than via the public switched telephone network (PSTN), also known as plain old telephone service (POTS). Overview The steps and principles involved in originating VoIP telephone calls are similar to traditional digital telephony and involve signaling, channel setup, digitization of the analog voice signals, and encoding. Instead of being transmitted over a circuit-switched network, the digital information is packetized and transmission occurs as IP packets over a packet-switched network. They transport media streams using special media delivery protocols t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Acquisitions By Cisco Systems
Cisco is an American computer networking company. Cisco made its first acquisition in 1993, which was followed by a series of further acquisitions. History Founded in 1984, Cisco did not acquire a company during the first seven years of its existence; but, on September 24, 1993, Cisco acquired Crescendo Communications, a LAN switching company. Following the first Cisco takeover purchase, acquisitions have constituted 50 percent of the company's business activity. The company's largest acquisition is the purchase of Scientific-Atlanta—a manufacturer of cable television, telecommunications and broadband equipment—for US$6.9 billion. The purchase represented the interest that Cisco had in Internet television, as spending on switches and routers decreased, and expanded the corporation's consumer product base after its prior acquisition of Linksys Inc., a producer of wireless networking products for homes and small businesses. Cisco chief executive officer (CEO) at the time, J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Audium (theater)
Audium is a sound art event that has been presented weekly in San Francisco since 1967. Audium is a creation of composer Stan Shaff that is performed on original equipment designed by Doug McEachern. It is played in a completely dark theater designed to heighten the spatial effects of sound and for "choreographing sound in space." Compositions are developed from acoustic and electronic instruments and from sounds of the natural world used as metaphors. Works are "sculpted" in space through 176 speakers. Early development The concepts gradually refined in Audium began with Shaff and McEachern's experimental electronic music performances in the late 1950s and early 1960s. In 1959, Stan Shaff met fellow musician and teacher Douglas McEachern, whose background in electronics enabled him to develop original equipment systems for live, spatial performances. Prior to Audium, Shaff and McEachern worked with Anna Halprin's Dancer's Workshop and Shaff worked with Seymour Locks, an artist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
