...T(X) and SONET Digital Hierarchy Digital Transmission Hierarchies are made up of two main structures of digital networks. These two structures are known as Synchronous and Plesiochronous hierarchies. These relate to the transmission standards for all public telecommunication networks. Plesiochronous tasks the higher level multiplexers with "bit stuffing" techniques which inserts one or more bits of data into a single transmission unit to produce a signal to the receiver. (Rouse, 2014) Synchronous Hierarchy has all multiplexer units operating in accordance with common source clocks. (Rouse, 2014) SONET (Synchronous Optical Network) is Under the Synchronous model in the North American Hierarchy. SONET was developed in the 1980s and ,much like T(x), it was designed to carry large amounts of data over long distances and uses fiber optic cabling to transmit data on the network at very high speeds. SONET is based on the fundamental rate of 50.84 MBPS defined as Synchronous Transport Signal Level 1, or STS-1, which contrasts the International Synchronous Digital Hierarchy fundamental rate. The International Synchronous Digital Hierarchy has a fundamental rate of 155.520 MBPS, defined as STM-1 (Synchronous Transport Module Level 1). (Goleniewski, 2007) T(x) or T-Carrier, is the network standard in the North American region for Plesiochronous Digital Hierarchy (PDH) and uses a rate of 64Kbps per channel. T(x) was developed in 1957 by AT&T to support voice transmission pulse-code modulation...
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...Digital Transmission Hierachies There are two hierarchical structures that exist for digital networks: Plesiochronous hierarchies and Synchronous hierarchies. In a Plesiochronous hierarchy, the higher level multiplex functions include "bit stuffing" techniques. This allows the input bit streams from I/O channels to use "free-running" clocks. The user's clock rate is propagated through the higher level multiplexer. Slip rates requirements between End-User multiplex equipment must still be met, for adequate performance of voice and particularly data. The digital hierarchy starts off with a basic Digital Signal level of 64 KBPS (DS0). Thereafter, all facility types are usually referred to as "T x", where "x" is the Digital Signal level within the hierarchy (e.g. T1 refers to the DS1 rate of 1.544 MBPS). Up to the DS3 rate, these signals are usually delivered from the provider on Twisted-Pair or Coaxial cables. North American T1 service providers often refer to the signal interface between the User and the Network as "DS-1" signals. In the case of User to User interfaces, the term "DSX-1" is used to describe those DS1 signals at the "cross-connect" point. Name Rate ---- ----------- DS0 64 KBPS DS1 1.544 MBPS DS1C 3.152 MBPS DS2 6.312 MBPS DS3 44.736 MBPS DS4 274.176 MBPS Synchronous Hierarchies In the late 1980s, synchronous network hierarchies were defined. In Synchronous networks, all multiplex functions operate using...
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...T(X) and SONET Hierarchy SONET Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are SMP’s that transfer digital information over optical fiber using Light Emitting Diodes, or LEDs. SONET allows for simultaneous transmission of a multitude of different circuits of different origin with a single framing protocol. The unit of framing in SONET is STS-3c, which stands for Synchronous Transport Signal, and the C stands for concatenated. This may also be referred to as OC-3c, which stands for Optical Carrier. This is determined by whether the signal is carried electronically or optically. In SDH, the base frame is referred to as STM-1, or Synchronous Transport Module, the 1 stands for the first level of the SDH hierarchy. The way the hierarchy is developed by multiplexing signals. For example, three STS-1 signals are multiplexed to for STS-3, and OC-3. Higher-speed circuits are formed by aggregated multiples of slower circuits. For the next hierarchy level, four STS-3 signals aggregated form STS-12c or OC-12c. This is done on each level to form the SONET hierarchy. T(x) Hierarchy The North American Signal hierarchy was developed in the 1960’s by AT&T, and was the world’s first digital voice system. The signal hierarchy defines the levels of multiplexing. Digital signals are assigned a carrier, which is then given a T(x) designation. The first hierarchy is the T-1 level, which has a 1.544 mbit/s speed. The second level is the T-2 level and has...
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...Sonet (synchronous optical network) Introduction SONET was developed to satisfy the requirements of continuously increasing data rate for various applications by ANSI. Sonet uses enormous potential bandwidth of optical fiber. ITU – T also developed a similar technique which is known as synchronous digital hierarchy (SDH). Sonet uses sync TDM technique with a master clock. The master clock is used for predictability. Sonet has high bandwidth availability and configuration facility which has its significant advantages: • Flexible architecture, so it can accommodate future applications. • Supports variety of transmission rate. • Standardized, so it can connect multiple vendor equipment. • A synchronous that greatly simplifies the interface to digital switches, digital cross connect switches and add drop multiplexers. • Increase in network reliability with decrease in network equipment. • Creates standard operation, administration and maintenance (OAM). Synchronization of digital signals To understand the concepts and details of SONET correctly, it is important to follow the meaning of synchronous, asynchronous, and plesiochronous. In synchronous signal, digital signal transitions occurs at the same rate with a possible phase difference. Propagation delays or jitter in the transmission network can cause propagation delay. In synchronous network all clocks are matched with master or primary clock. In plesiochronous digital signals transitions happen at almost the...
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...are the various modulation techniques? Begin your explanation with frequency-shift keying and move to multilevel QAM. During this week’s readings I have found 4 different modulation techniques: Amplitude modulations, frequency modulation, phase modulation, and quadrature amplitude modulation. While these have different modulation schemes that branch out, these are the primary used modulations I have found. Amplitude modulation is when different amplitudes are used to represent the digital bitstream in analog format. Modems rely on amplitude modulation to determine the high amplitude that is represented by ones and low amplitudes that are represented by zeros. They also rely on amplitude modulation to determine the difference in the amplitudes so the receiving device can put out the message in the correct way. Frequency modulation is also known as FSK, or frequency-shift key. FSK’s uses two different frequencies to distinguish between a mark digital 1 and a space digital 0 when transmitting on an analog line. It is used on modems that operate at 1,200bps or slower (Goleniewski, 2007). Phase modulation modifies a sine wave, also known as a carrier, to allow it to carry information. The phase of the sine wave is changed to fit the type of information that is being transferred. Phase modulation can be paired with carrierless amplitude for ADSL, or Asymmetrical DSL. Last Quadrature Amplitude Modulation is a “single-carrier scheme that modulates both the...
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...(WANs) Objectives By the end of this lesson, you will be able to: Describe the characteristics and functions of wide area networks (WANs). Define basic signaling and transmission terminology, including analog and digital signals, Digital Signal Level Zero (DS0), broadband, baseband, multiplexing, and Digital Signal Hierarchy (DSH). Distinguish between circuit switching and packet switching, and identify various circuit-switching and packet-switching technologies. Describe the characteristics and performance of dial-up connections, including POTS and Integrated Services Digital Network (ISDN). Describe the characteristics and performance of direct connections, including leased T-carrier and E-carrier lines, cable Internet, Digital Subscriber Line (DSL), LAN connections, and fiber to the x (FTTx). Describe the characteristics and functions of Synchronous Optical Network (SONET). Describe the characteristics and functions of Asynchronous Transfer Mode (ATM). 2-2 Local Area Networks (LANs) Pre-Assessment Questions 1. Which of the following is faster than T1? a. b. c. d. 2. E1 ISDN BRI DS0 DS1 Which type of transmission uses a single channel? a. b. c. d. Broadband Digital Subscriber Line (DSL) Baseband Cable modem 3. How are digital signals measured? © 2012 CertPRESS, a division of Certification Partners, LLC — All Rights Reserved. Version 7.0 Lesson 2: Wide Area Networks (WANs) 2-3 Introduction to Wide Area Networks (WANs) wide...
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...This synchronization system allows entire inter- country networks to operate synchronously, greatly reducing the amount of buffering required between elements in the network. Both SONET and SDH can be used to encapsulate earlier digital transmission standards, such as the PDH standard, or they can be used to directly support either Asynchronous Transfer Mode (ATM) or so-called packet over SONET/SDH (POS) networking. As such, it is inaccurate to think of SDH or SONET as communications protocols in and of themselves; they are generic, all-purpose transport containers for moving both voice and data. The basic format of a SONET/SDH signal allows it to carry many different services in its virtual container (VC), because it is...
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...2005-2007 Class 12 (AHSEC) 59% Dispur Govt. H.S. School, 2005 Class 10 (SEBA) 75% WORK EXPERIENCE Tradeline Corporation, (01.01.2013 - Present) Guwahati, Assam Job Position: Service Engineer (North-East) Digital Check Lab, (22.02.2012 – 15.12.2012) Guwahati, Assam Job Position: Marketing Executive Projects: GPS/GPRS vessel tracking in Inland Water Authority of India (IWAI). Developing solar powered Device Tracker Module for IWAI. ACTIVITIES BSNL, RTTC Guwahati, Assam, India Project: Optical Fiber Systems and Synchronous Digital Hierarchy (5 ½ month training). Tocklai Experimental Station, Tea Research Association (TRA), Jorhat, Assam. Project: Section Wise Yield of Tea and Its Variation (1998-2008) (2 ½ month training). TECHNICAL SKILLS Course Work: VLSI, 8086 microprocessor, Mobile Communications, Microelectronics, Satellite Communication, Control System, Digital Signal Processing, Signal and Systems, RF and Microwaves, EMFW, Communication Systems, DECO, Image Processing. Programming Language: C, C++, VB.NET, HTML, SQL, UNIX Tools: AUTOCAD,Google SketchUP, ASP.net, SQL SERVER 2006, ORACLE, MS Office. PROJECTS HOME AUTOMATION USING DTMF OPTICAL FIBER SYSTEMS AND SYNCHRONOUS DIGITAL HIERARCHY AREA OF INTEREST Telecomm. Industry, Electronics Industry, Networking or Software Industry. Hobbies: Painting, Travelling & making electronics projects. EXTRA CURRICULAR ACTIVITIES Get 1st position in International...
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...Analog and Digital Comparison Learning Team D: Juan C. Godinez, Luke Wade, Jonathan Selinksi NCT/362 March 16th, 2015 Richard Bohn Analog and Digital Comparison Data, media, networking and transfer technology has evolved immensely throughout the years. When it comes to transmissions, two prerequisites must be satisfied to have successful communication. The first prerequisite is understandability. The transmitter and receiver must speak the same language. The second prerequisite is the capability to detect errors as they occur and to have some procedure for resolving those errors. (Goleniewski, L., 2007). Picture this similar to the different languages people can speak all over the world. Without proper translation and understanding, the conversation is pointless; this analogy is similar for analog and digital transmissions. Beginning with an analog signal, which is a continuous variable along amplitude and frequency. Analog circuits need to have a defined frequency band in which it operates. Different modulation schemes can vary the speed in which they operate, the quality of wire they require, the immunity to noise, and their overall complexity. The variety of modulation schemes in existence can be a disadvantage as this means many incompatibilities can exist within a single application. Such modulations include: * Amplitude modulation (AM) - modem relies on amplitude and associates high amplitude/zeros with low amplitude. Amplitude modulation can be demodulated...
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...Synchronous Ethernet and IEEE 1588v2 Technology White Paper Issue Date 01 2012-10-30 HUAWEI TECHNOLOGIES CO., LTD. Copyright © Huawei Technologies Co., Ltd. 2012. All rights reserved. No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd. Trademarks and Permissions and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders. Notice The purchased products, services and features are stipulated by the contract made between Huawei and the customer. All or part of the products, services and features described in this document may not be within the purchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied. The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty of any kind, express or implied. Huawei Technologies Co., Ltd. Address: Huawei Industrial Base Bantian, Longgang Shenzhen 518129 People's Republic of China Website: http://enterprise...
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...Analog and Digital Comparison Paper Current technology utilizes many different types of transmission cable such as fiber optics, coaxial cable, and twisted pair copper wire. These different types of cables use different communications techniques that maximize their efficiency. For instance, fiber optics can carry digital signals over long distances without amplification or repeaters required. Copper wire, on the other hand, carrying analog signals requiring amplification and noise corrections along the way in much shorter intervals. The result is there is a mix of transmission lines that require special software and equipment such as codecs and modems to convert and move data from one point to another. Codecs and Modems The most common form of analog to digital conversions uses multiplex devices and coder-decoder devices otherwise known as codecs. These programs receive analog signals from sine waves such as audio communications and code them as digital signals. These signals then travel to other locations with codec or modem devices that decode or decompress the data back to analog signals. Digital devices use modems or combinations of codecs and modems to modulate the data signals to analog signals to travel to other modems for demodulation back to digital data. The codec is “software that is used to compress or decompress a digital media file, such as a song or video” (Microsoft, 2014). This process is the same in telecommunications systems, which consist of the encoder...
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...Analog and Digital Comparison Paper Current technology utilizes many different types of transmission cable such as fiber optics, coaxial cable, and twisted pair copper wire. These different types of cables use different communications techniques that maximize their efficiency. For instance, fiber optics can carry digital signals over long distances without amplification or repeaters required. Copper wire, on the other hand, carrying analog signals requiring amplification and noise corrections along the way in much shorter intervals. The result is there is a mix of transmission lines that require special software and equipment such as codecs and modems to convert and move data from one point to another. Codecs and Modems The most common form of analog to digital conversions uses multiplex devices and coder-decoder devices otherwise known as codecs. These programs receive analog signals from sine waves such as audio communications and code them as digital signals. These signals then travel to other locations with codec or modem devices that decode or decompress the data back to analog signals. Digital devices use modems or combinations of codecs and modems to modulate the data signals to analog signals to travel to other modems for demodulation back to digital data. The codec is “software that is used to compress or decompress a digital media file, such as a song or video” (Microsoft, 2014). This process is the same in telecommunications systems, which consist of the encoder...
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...به نام خداوند جان و خرد گروه مهندسی کامپيوتر عنوان مقاله: آشنایی با سیستم های SDH تهیه و تنظیم: سجاد معظمی استاد راهنما: مهندس افراسیابی تابستان 91 کليه حقوق مادي مرتبط بر نتايج مطالعات، ابتکارات و نوآوريهاي ناشي از تحقيق موضوع اين مقاله متعلق به دانشگاه صنعتی همدان است. چکیده: این مقاله در مورد سیستم های مخابراتی SDH بحث می کند. در این مقاله با ساختار این سیستم، مقدمات آن، و کاربرد های آن در دنیای صنعت آشنا خواهیم شد. مقدمه ای در مورد مالتی پلکسینگ و سیستم قدیمی PDH و آشنایی با معایب آن و در نهایت با سیستم SDH و مزایای آن نسبت به سیستم قدیمی بحث خواهد شد. کلمات کلیدی: SDH, PDH, MUX، فریم بندی، مالتی پلکسینگ فهرست مطالب عنوان | صفحه | | | 1 فصل اول 1 1-1 مقدمه 1 1-2 مروری بر PDH 1 1-3 معایب سیستم سنتی PDH 3 2 فصل دوم 6 2-1 مقدمه 6 2-2 ویژگیهای اصلیSDH 6 2-3 مزایایSDH 8 2-4 معایب SDH 10 3 سرواژه ها 11 3 مراجع 12 فصل اول ساختار SDH 1-1 مقدمه سیستم SDH یک سیستم انتقال برای سرعت های بالاست. سیستم های مخابرات نوری ظرفیت بالایی که خصوصیت سیگنالهای دیجیتال شامل فریم، روش مالتی پلکسینگ، سلسله مراتب سرعت های دیجیتال و غیره را تعریف می کنند. قبل از ورود به جزئیات SDH لازم است که یک تصور اساسی درباره تکنولوژی ماقبل آن یعنی PDH داشته باشیم. 1-2 مروری بر PDH سیگنال PDH با یک سرعت انتقال بالاتر به وسیله مالتی پلکسینگ چندین سیگنال سرعت پایین تر بدست می آید. در حال حاضر سلسله مراتب PDH سه شاخه دارد: 1. استاندارد اروپایی 2. استاندارد آمریکای شمالی 3. استاندارد ژاپنی شکل زیر سلسله مراتب اروپایی PDH...
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...| Analog and Digital Comparison | NTC/362 Fundamentals in Networking | EDWARD BROWN | Jose Giralt | 3/18/2013 | | A signal is simply the transmission of data from one place to another place. In our day to day life we deal with various signals constantly like signals from music, power lines, telephones, and cellular devices. Analog and digital are two kinds of signals which are used for the transmission of information from source to destination. Usually the information to be transmitted from one place to another is either audio or video. This information signal is then transformed into those signals which can be transmitted via different channels. For the analog format, the data is transformed into electrical pulses with varying amplitude while for the digital format; the data is transformed into binary format representing two amplitudes. We have various such equipment like analog or digital phones, fax machines, modems, clocks, watches etc. Analog technology is the older one and has been used for decades. It is cheap too but the problem with analog signals is that there is a limitation on the size of the data that can be transmitted at any given point of time. With the advent of digital technology many improvements and new techniques have been introduced. Now days almost every appliance or equipment is based on digital technology. In this, the transmitter translate the data into binary form and the receiver re assemble and produces the...
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...Analog and Digital Comparison Technologies for analog-to-digital and digital-to-analog conversions There is no actual all analog or all digital telecommunications going on technologically today (Goleniewsk & Wilson Jarrett, 2007, Chapter Chapter 1, Analog Versus Digital Transmission). One day, developers hope to make the network 100% digital. Connecting to the internet or just making a call to your mother two states over is a mixture of both when it comes to communicating from one terminal to the next. That being said, it takes codecs and modems for a successful conversion to occur. Say you are calling another state from a land line. This call will start out analog at your telephone and then must be converted to digital. When you pick your phone up, it connects to a codec. Your voice can range from 100Hz to 10,000Hz depending on many factors. The average Hz a phone company will allot is 4,000 which works for virtually all people. Codec is short for coder-decoder and it works by minimizing the amount of bits per second that will carry the voice to the multiplexer. In the case of a cellular network, the data will have to be compressed even further so that the most efficient transmission can occur. The codec will then transfer the data to a multiplexer. This particular multiplexer is a TDM (time division multiplexer). This will allow for one channel to be open at a time. This does make sense since it would not be good to take over a phone line once it is being...
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