Synchronous optical networking (SONET) and synchronous digital hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams synchronously over optical fiber using lasers or highly coherent light from light-emitting diodes (LEDs). At low transmission rates data can also be transferred via an electrical interface. The method was developed to replace the plesiochronous digital hierarchy (PDH) system for transporting large amounts of telephone calls and data traffic over the same fiber without the problems of synchronization.
In telecommunications and computer networks, multiplexing is a method by which multiple analog or digital signals are combined into one signal over a shared medium. The aim is to share a scarce resource. For example, in telecommunications, several telephone calls may be carried using one wire. Multiplexing originated in telegraphy in the 1870s, and is now widely applied in communications. In telephony, George Owen Squier is credited with the development of telephone carrier multiplexing in 1910.
Time-division multiplexing (TDM) is a method of transmitting and receiving independent signals over a common signal path by means of synchronized switches at each end of the transmission line so that each signal appears on the line only a fraction of time in an alternating pattern. It is used when the bit rate of the transmission medium exceeds that of the signal to be transmitted. This form of signal multiplexing was developed in telecommunications for telegraphy systems in the late 19th century, but found its most common application in digital telephony in the second half of the 20th century.
In fiber-optic communications, wavelength-division multiplexing (WDM) is a technology which multiplexes a number of optical carrier signals onto a single optical fiber by using different wavelengths of laser light. This technique enables bidirectional communications over one strand of fiber, as well as multiplication of capacity.
Eupithecia is a large genus of moths of the family Geometridae. There are hundreds of described species, found in all parts of the world, and new species are discovered on a regular basis.
The lime-speck pug is a moth of the family Geometridae. It is a common species throughout the Palearctic region, the Near East and North Africa.
The common pug(Eupithecia vulgata) is a moth of the family Geometridae. It is a common species across the Palearctic region, the Near East and North Africa. It ranges from the Atlantic coast of Ireland and Portugal across Europe, the Middle East and Central Asia to the Russian Far East (Priamurje) and Korea.
The juniper pug or juniper looper(Eupithecia pusillata) is a moth of the family Geometridae. It is found throughout the Palearctic and Nearctic regions and the Near East.
ITU-T defines an Optical Transport Network (OTN) as a set of Optical Network Elements (ONE) connected by optical fiber links, able to provide functionality of transport, multiplexing, switching, management, supervision and survivability of optical channels carrying client signals. An ONE may Re-time, Re-Amplify, Re-shape (3R) but it does not have to be 3R – it can be purely photonic.
The alpine pine vole is a species of rodent in the family Cricetidae. It is found in Austria, France, Italy, Serbia and Montenegro, and Switzerland.
Eupithecia innotata, the angle-barred pug, is a moth of the family Geometridae. It ranges from Spain in the west to western Siberia and central Asia in the east.
The larch pug is a moth of the family Geometridae. The species can be found in Europe, the Ural Mountains, West and Central Siberia, the Altai Mountains, Transbaikalia, Yakutia, the Far East, Mongolia, Korea, Japan and in North America, from Yukon and Newfoundland to New York and Arizona.
Eupithecia simpliciata, the plain pug, is a moth of the family Geometridae. It is found in the Palearctic ecozone, from western Europe to north-western China (Xinjiang).
Eupithecia venosata, the netted pug, is a moth of the family Geometridae. It was first described by Johan Christian Fabricius in 1787. It is found across the Palearctic ecozone from Portugal and Morocco in the west to the Lake Baikal in Siberia and Afghanistan and Pakistan in the east.
Eupithecia pernotata, or Guenée's pug, is a moth of the family Geometridae. The species was first described by Achille Guenée in 1857. It is known from the Alps, through Romania to southern Russia. It is also found in Finland.
Orbital angular momentum (OAM) multiplexing is a physical layer method for multiplexing signals carried on electromagnetic waves using the orbital angular momentum of the electromagnetic waves to distinguish between the different orthogonal signals.
Eupithecia quadripunctata is a moth in the family Geometridae. It is found in India, Pakistan, Nepal, Russia, China, Taiwan, Korea, Japan and northern Thailand.
Eupithecia variostrigata is a moth in the family Geometridae. It is widespread in the western Palaearctic, ranging from Spain to the western Pamirs in the east.
Eupithecia silenicolata is a moth in the family Geometridae. It is found from southern Europe and Morocco to western Asia, Iran and Pakistan. In the north, the range extends to southern Switzerland, Austria and northern Italy.
Eupithecia graefi, or Graef's pug, is a moth in the family Geometridae. The species was first described by George Duryea Hulst in 1896. It is found in North America from south-western Alberta west to Vancouver Island, north to Alaska and south to California. The habitat consists of wooded areas.
