Synchronous Digital Hierarchy. An ITU-T standard for multiplexing and demultiplexing of optical signals that run over fiber optic infrastructure. SDH is classified based on its traffic carrying capacity into STM-1 (155 Mbps), STM-4 (622 Mbps), and so on. SDH is used outside North America (mainly in Europe and Asia). North American counterpart is called SONET. SDH provides transport for any kind of access networks. Also see multiplexing and SONET.
(Synchronous Digital Hierarchy) SDH has many advantages over existing transmission technologies including flexibility in managing the transmission, reconfiguration and control and switching at data rates to 622Mbit/s and beyond
SDH is a set of standards for optic data transmission systems. (Synchronous digital hierarchy) SDH makes it easier to use different manufacturer's equipment together, and also benefits the customers by minimizing the amount of equipment required for different telecommunication applications. SDH also improves operation security.
Synchronous Digital Hierarchy. Before SDH, networks were extremely rigid and creating a new link between two points was time consuming. It could take months to set up new services. In the late 1980s operators and suppliers standardized first on SONET (Synchronous Optical Network)and then SDH standards for optical transmission. By using Add/Drop Multiplexers (ADM) new signals can be added to or dropped from the network quickly and easily. The network can then be monitored centrally, adding to both flexibility and reliability. When a fault does occur, the traffic can be re-routed so quickly that the user does not even realise there was anything wrong.
Synchronous Digital Hierarchy. a method of digital transmission where the data is packed in containers which are synchronised in time enabling relatively simple multiplexing and de-multiplexing at the transmitting and receiving ends.
Synchronous Digital Hierarchy. Synchronous transmission and multiplexing system for telecommunications networks. It operates at speeds between 155 Mbit/s to 2.54 Gbit/s. SDH will be the future transmission system in the telecom network.
Synchronous Digital Hierarchy. A standard technology for synchronous data transmission using optical media as the physical transport for high speed long-haul networks. It is the international equivalent of Synchronous Optical Network (SONET). SDH uses the following Synchronous Transport Modules (STM) and rates: STM-1 (155 megabits per second), STM-4 (622 Mbps), STM-16 (2.5 gigabits per second), and STM-64 (10 Gbps).
Synchronous Digital Hierarchy. SDH is an international standard for synchronous data transmission over fiber optic cables. The North American equivalent of SDH is SONET. SDH defines a standard rate of transmission at 155.52 Mb/s, which is equivalent to a rate of OC-3.
Synchronous Digital Hierarchy. Synchronic transmission and multiplex system for telecommunication networks. It operates at speeds of between 155 Mbits/s amd (so far) 2.54 Gbits/s. SDH will be the future transmission system in the telecommunications network and will gradually replace PDH.
Synchronous Digital Hierarchy Standardized by the ITU, SDH is a family of digital carrier rates. SDH is the term used by the ITU to refer to SONET OC rates, as they are called in the United States. The basic SDH building block is a rate of 155.52 Mbps, called STM-1.
It is a standard of data transmission by optical medium, realized through hierarchic consistent file of multiplexers. The main technology of information transmission in transport fiber-optical networks from 50 Mbit/s to 2,4 Gbit/s.
Short for ynchronous igital ierarchy, an international standard for synchronous data transmission over fiber optic cables. The North American equivalent of SDH is SONET. SDH defines a standard rate of transmission at 155.52 Mbps, which is referred to as STS-3 at the electrical level and STM-1 for SDH. STM-1 is equivalent to SONET's Optical Carrier (OC) levels -3.
Synchronous Digital Heirarchy. There are two main transmission rate standards in the world,CEPT (European) and North American (US). SDH is recommended by CDITT to establish a universal digital network standard for the coming of the ISDN age. Some of the advantages of SDH: Simplified multiplexing/demultiplexing; direct access to lower speed tributaries; easy growth to higher bit rates in step with evolution of transmission technology.
Synchronous Digital Hierarchy. A method used for multiplexing many circuits with a low bit rate onto fewer circuits with a higher bit rate, and vice-versa (de-multiplexing). Used primarily in the telecomms industry to carry telephony traffic. This network can also be used to carry IP traffic.
Synchronous Digital Hierarchy. SDH defines a number of "containers," each corresponding to an existing plesiochronous rate (1.5, 2, 6, 34, 45 and 140 Mbps). Each "container" has some control information known as "Path Overhead" (POH) added to it. The POH allows the network operator to achieve end-to-end path monitoring. Together the container and the path overhead form a "Virtual Container" (VC) in Europe or "Virtual Tributary" (VT) in North America.
Synchronous Digital Hierarchy. European standard that defines a set of rate and format standards that are transmitted using optical signals over fiber. SDH is similar to SONET, with a basic SDH rate of 155.52 Mbps, designated at STM-1. See also SONET and STM-1.
synchronous digital hierarchy. the ITU–T–defined world standard of transmission whose base transmission level is 52 Mbps (STM–0) and is equivalent to SONET's STS–1 or OC–1 transmission rate; SDH standards w
Synchronous Digital Hierarchy. This is a method of digital transmission. It exists where the data is packed in containers. These are then synchronised in time, thus enabling relatively simple multiplexing and also demultiplexing at the receiving and transmitting ends.
Similar to "closed captioning," but SDH does not require a compatible television set to display the text of dialogue and sound effects within a film. The "subtitle" option on the DVD remote activates English subtitles which correspond to the film.