Tektronix sdh glos free download

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Glossary & ITU TStandards CT850 Test Set SDH/PDH, Jitter/Wander Included in this section along with the glossary of terms is a listing of ITU T standards for SDH and PDH. Three sets of terms are arranged at the beginning of this section because it is important to see that they are not equivalent terms, which is how they get used in normal discussions. They are: Add/ Drop The process where a part of the information carried in a transmission system is extracted (dropped) at an intermediate point and different information is inserted (added) for subse- quent transmission. The remaining traffic passes straight through the multiplexer without additional processing. Map/ Demap A term for multiplexing, implying more visibility inside the resultant multiplexed bit stream than available with convention- al asynchronous techniques. Multiplex/ Demultiplex Multiplex (MUX) To transmit two or more signals over a single channel. Demultiplex (DEMUX) To separate two or more signals previously combined by compatible multiplexing equipment. Demultiplexing A process applied to a multiplex signal for recovering signals combined within it and for restoring the distinct individual channels of the signals. An alphabetical list of glossary terms follows. CT850 Test Set SDH/PDH, Jitter/Wander User Manual Glossary 1 Glossary Add/Drop Multiplexer (ADM) A multiplexer capable of extracting and inserting lower rate signals from a higher rate multiplexed signal without complete- ly demultiplexing the signal. Administrative Unit (AU) An Administrative Unit is the information structure which provides adaptation between the higher order path layer and the Multiplex Section layer. The Virtual Container (VC) plus the pointers (H1, H2, H3 bytes) is called the Administrative Unit (AU). AIS (Alarm Indicating Signal) A code sent downstream indicating an upstream failure has occurred. AMI Alternate Mark Inversion. The line coding format in transmis- sion systems where successive ones (marks) are alternatively inverted (sent with polarity opposite that of the preceding mark). Analog Jitter Out A signal that contains the demodulated jitter from a line or clock input. ANSI American National Standards Institute. A standards setting, non government organization, which develops and publishes standards for "voluntary" use in the United States. Asynchronous A networ