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Unidirectional Lightweight Encapsulation
The Unidirectional Lightweight Encapsulation (ULE) is a Data link layer protocol for the transportation of network layer packets over MPEG transport streams. Because of the very low protocol overhead, it is especially suited for IP over Satellite services (where every bit counts). Such a system is for example DVB-S. However, ULE can also be used in the context of DVB-C and DVB-T, theoretically in every system which is based on MPEG transport streams (e.g., ATSC). ULE has been engineered by the IP over DVB (ipdvb) working group of the Internet Engineering Task Force (IETF) and has been standardized in RFC 4326. Another encapsulation method is Multiprotocol Encapsulation (MPE) which was developed and standardized by the DVB project. See also * MPEG-2 * Generic Stream Encapsulation (GSE) * Multiprotocol Encapsulation (MPE) * Datacasting * Internet Protocol Datacasting (IPDC) for DVB-H * UDcast * Interactive television Interactive television is a form of media convergence, addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Data Link Layer
The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between nodes on a network segment across the physical layer. The data link layer provides the functional and procedural means to transfer data between network entities and may also provide the means to detect and possibly correct errors that can occur in the physical layer. The data link layer is concerned with local delivery of frames between nodes on the same level of the network. Data-link frames, as these protocol data units are called, do not cross the boundaries of a local area network. Inter-network routing and global addressing are higher-layer functions, allowing data-link protocols to focus on local delivery, addressing, and media arbitration. In this way, the data link layer is analogous to a neighborhood traffic cop; it endeavors to arbitrate between parties contending for access to a medium, without con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Generic Stream Encapsulation
Generic Stream Encapsulation, or GSE for short, is a Data link layer protocol defined by DVB. GSE provides means to carry packet oriented protocols such as IP on top of uni-directional physical layers such as DVB-S2, DVB-T2 and DVB-C2. GSE provides additional features beyond the pure carriage of IP datagrams that increase the protocol flexibility and applicability. Some key GSE functions/characteristics are: * Support for multi-protocol encapsulation (IPv4, IPv6, MPEG, ATM, Ethernet, 802.1pQ VLANs, etc.) * Transparency to network layer functions, including IP encryption and IP header compression. * Support of several addressing modes. In addition to the 6-byte MAC address (including multicast and unicast), it supports a MAC address-less mode, and an optional 3-byte address mode. * A mechanism for fragmenting IP datagrams or other network layer packets over Base Band frames to support ACM/ VCM. * Support for hardware filtering. * Extensibility: additional link protocols can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Broadcast Engineering
Broadcast engineering is the field of electrical engineering, and now to some extent computer engineering and information technology, which deals with radio and television broadcasting. Audio engineering and RF engineering are also essential parts of broadcast engineering, being their own subsets of electrical engineering. Broadcast engineering involves both the Television studio, studio and transmitter aspects (the entire airchain), as well as remote broadcasts. Every Broadcast network, station has a broadcast engineer, though one may now serve an entire station group in a city. In small media markets the engineer may work on a contract basis for one or more stations as needed. Duties Modern duties of a broadcast engineer include maintaining broadcast automation systems for the studio and automatic transmission systems for the transmitter physical plant, plant. There are also important duties regarding Radio masts and towers, radio towers, which must be Preventive maintenanc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG
The Moving Picture Experts Group (MPEG) is an alliance of working groups established jointly by International Organization for Standardization, ISO and International Electrotechnical Commission, IEC that sets standards for media coding, including compression coding of audio compression (data), audio, video compression, video, graphics, and Compression of Genomic Sequencing Data, genomic data; and transmission and Container format (digital), file formats for various applications.John Watkinson, ''The MPEG Handbook'', p. 1 Together with Joint Photographic Experts Group, JPEG, MPEG is organized under ISO/IEC JTC 1/ISO/IEC JTC 1/SC 29, SC 29 – ''Coding of audio, picture, multimedia and hypermedia information'' (ISO/IEC Joint Technical Committee 1, Subcommittee 29). MPEG formats are used in various multimedia systems. The most well known older MPEG media formats typically use MPEG-1, MPEG-2, and MPEG-4 AVC media coding and MPEG-2 systems MPEG transport stream, transport streams an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interactive Television
Interactive television is a form of media convergence, adding data services to traditional television technology. It has included on-demand delivery of content, online shopping, and viewer polls. Interactive TV is an example of how new information technology can be integrated vertically into established technologies and commercial structures. History Prior to the development of interactive television, interaction could only be simulated. In the 1950s, there were limited efforts to provide an illusion of interactive experience, most overtly with ''Winky Dink and You'', which encouraged viewers to draw on a vinyl sheet they would attach to a television set. QUBE operated an interactive cable television service in Ohio from 1977 to 1984. An interactive video-on-demand (VOD) television service was proposed in 1986 in Japan, where there were plans to develop an "Integrated Network System" service. It was intended to include various interactive services, including videotelephony, home ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UDcast
UDcast was a company that provided products for Internet Protocol (IP) over broadcast media. It developed technology for IP networks over satellite and servers to provide television on mobile networks. History UDcast was involved in international standards organisations such as ETSI and the Internet Engineering Task Force. UDcast was founded in June 2000 by members of the INRIA research center who had helped develop Unidirectional Link Routing (the ''UD'' stands for unidirectional, and the ''cast'' for broadcast). The mechanism was published in 2001 as number 3077 in the Request for Comments series. Founders included Antoine Clerget, Patrick Cipière, Emmanuel Duros, and Luc Ottavj. From at least 2003 through 2007, Hubert Zimmermann served as chief executive officer. UDcast marketed wide-area network optimization appliances optimized for satellite infrastructures, with optimizations targeted at some specific satellite markets. They used acronyms such as DVB-H, DVB-SH, ATSC and W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVB-H
DVB-H (Digital Video Broadcasting - Handheld) is one of three prevalent mobile TV formats. It is a technical specification for bringing broadcast services to mobile handsets. DVB-H was formally adopted as ETSI standard EN 302 304 in November 2004. The DVB-H specification (EN 302 304) can be downloaded from the official DVB-H website. From March 2008, DVB-H is officially endorsed by the European Union as the "preferred technology for terrestrial mobile broadcasting". The major competitors of this technology are Qualcomm's MediaFLO system, the 3G cellular system based MBMS mobile-TV standard, and the ATSC-M/H format in the U.S. DVB-SH (Satellite to Handhelds) now and DVB-NGH (Next Generation Handheld) in the future are possible enhancements to DVB-H, providing improved spectral efficiency and better modulation flexibility. DVB-H has been a commercial failure, and the service is no longer on-air. Ukraine was the last country with a nationwide broadcast in DVB-H, which began trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internet Protocol Datacasting
Datacasting (data broadcasting) is the broadcasting of data over a wide area via radio waves. It most often refers to supplemental information sent by television stations along with digital terrestrial television (DTT), but may also be applied to Digital data, digital Signalling (telecommunication), signals on analog TV or radio. It generally does not apply to data which is inherent to the medium, such as PSIP data which defines virtual channels for DTT or direct broadcast satellite systems; or to things like cable modem or satellite modem, which use a completely separate channel for data. Overview Datacasting often provides news, weather, traffic, stock market, and other information which may or may not relate to the programs it is carried with. It may also be interactive, such as Video game, gaming, shopping, or education. An electronic program guide is usually included, although this stretches the definition somewhat, as this is often considered inherent to the digital bro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Datacasting
Datacasting (data broadcasting) is the broadcasting of data over a wide area via radio waves. It most often refers to supplemental information sent by television stations along with digital terrestrial television (DTT), but may also be applied to digital signals on analog TV or radio. It generally does not apply to data which is inherent to the medium, such as PSIP data which defines virtual channels for DTT or direct broadcast satellite systems; or to things like cable modem or satellite modem, which use a completely separate channel for data. Overview Datacasting often provides news, weather, traffic, stock market, and other information which may or may not relate to the programs it is carried with. It may also be interactive, such as gaming, shopping, or education. An electronic program guide is usually included, although this stretches the definition somewhat, as this is often considered inherent to the digital broadcast standard. The ATSC, DVB and ISDB standards ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG-2
MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic video coding format, coding of moving pictures and associated audio information". It describes a combination of Lossy compression, lossy video compression and Lossy compression, lossy audio data compression methods, which permit storage and transmission of movies using currently available storage media and transmission bandwidth. While MPEG-2 is not as efficient as newer standards such as H.264/AVC and HEVC, H.265/HEVC, backwards compatibility with existing hardware and software means it is still widely used, for example in over-the-air digital television broadcasting and in the DVD-Video standard. Main characteristics MPEG-2 is widely used as the format of digital television signals that are broadcast by terrestrial television, terrestrial (over-the-air), Cable television, cable, and direct broadcast satellite Television, TV systems. It also specifies the format of movies and other programs th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MPEG Transport Stream
MPEG transport stream (MPEG-TS, MTS) or simply transport stream (TS) is a standard digital container format for transmission and storage of audio, video, and Program and System Information Protocol (PSIP) data. It is used in broadcast systems such as DVB, ATSC and IPTV. Transport stream specifies a container format encapsulating packetized elementary streams, with error correction and synchronization pattern features for maintaining transmission integrity when the communication channel carrying the stream is degraded. Transport streams differ from the similarly-named MPEG program stream in several important ways: program streams are designed for reasonably reliable media, such as discs (like DVDs), while transport streams are designed for less reliable transmission, namely terrestrial or satellite broadcast. Further, a transport stream may carry multiple programs. Transport stream is specified in '' MPEG-2 Part 1, Systems'', formally known as ''ISO/IEC standard 13818- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multiprotocol Encapsulation
{{IPstack Multiprotocol Encapsulation, or MPE for short, is a Data link layer protocol defined by DVB which has been published as part of ETSI EN 301 192. It provides means to carry packet oriented protocols (like for instance IP) on top of MPEG transport stream (TS). Another encapsulation method is Unidirectional Lightweight Encapsulation (ULE) which was developed and standardized within the IETF as RFC 4326. Protocol Outline MPE uses MPEG-2 Private Table sections to carry the user datagrams. The section header is used to convey: * the frame's destination MAC address * optional ISO/IEC 8802-2 Logical Link Control (LLC) and ISO/IEC 8802-1 Sub-Network Attachment Point (SNAP) information * a payload scrambling indication * a MAC address scrambling indication MAC addresses from 1 to 6 bytes length may be used. The format of MPEG-2 DSM-CC sections happens to be compatible with DVB MPE. MPE-based IP Service Offerings Service Architecture A complete IP service offering over M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
