The Telephone Network
Total Page：16
File Type：pdf, Size：1020Kb
Load more
Recommended publications
-
How to Choose the Right Cable Category
How to Choose the Right Cable Category Why do I need a different category of cable? Not too long ago, when local area networks were being designed, each work area outlet typically consisted of one Category 3 circuit for voice and one Category 5e circuit for data. Category 3 cables consisted of four loosely twisted pairs of copper conductor under an overall jacket and were tested to 16 megahertz. Category 5e cables, on the other hand, had its four pairs more tightly twisted than the Category 3 and were tested up to 100 megahertz. The design allowed for voice on one circuit and data on the other. As network equipment data rates increased and more network devices were finding their way onto the network, this design quickly became obsolete. Companies wisely began installing all Category 5e circuits with often three or more circuits per work area outlet. Often, all circuits, including voice, were fed off of patch panels. This design allowed information technology managers to use any circuit as either a voice or a data circuit. Overbuilding the system upfront, though it added costs to the original project, ultimately saved money since future cable additions or cable upgrades would cost significantly more after construction than during the original construction phase. By installing all Category 5e cables, they knew their infrastructure would accommodate all their network needs for a number of years and that they would be ready for the next generation of network technology coming down the road. Though a Category 5e cable infrastructure will safely accommodate the widely used 10 and 100 megabit-per-second (Mbits/sec) Ethernet protocols, 10Base-T and 100Base-T respectively, it may not satisfy the needs of the higher performing Ethernet protocol, gigabit Ethernet (1000 Mbits/sec), also referred to as 1000Base-T. -
Modem and Networking Compaq Notebook Series
267639-001.book Page i Friday, January 18, 2002 8:31 AM b Modem and Networking Compaq Notebook Series Document Part Number: 267639-001 April 2002 This guide describes the modem and networking features on the notebook and explains how to connect a modem cable and a network cable. It also provides instructions for using the modem when travelling internationally. 267639-001.book Page ii Friday, January 18, 2002 8:31 AM © 2002 Compaq Information Technologies Group, L.P. Compaq, the Compaq logo, Evo, and Presario are trademarks of Compaq Information Technologies Group, L.P. in the U.S. and/or other countries. Microsoft and Windows are trademarks of Microsoft Corporation in the U.S. and/or other countries. All other product names mentioned herein may be trademarks of their respective companies. Compaq shall not be liable for technical or editorial errors or omissions contained herein. The information is provided “as is” without warranty of any kind and is subject to change without notice. The warranties for Compaq products are set forth in the express limited warranty statements accompanying such products. Nothing herein should be construed as constituting an additional warranty. Modem and Networking Guide First Edition April 2002 Document Part Number: 267639-001 267639-001.book Page iii Friday, January 18, 2002 8:31 AM Contents 1 Using an Internal Modem Connecting the Modem Cable . 1–2 Using the RJ-11 Cable. 1–2 Using a Country-Specific Modem Cable Adapter. 1–4 Adding New Locations When Travelling . 1–6 Solving Travel Connection Problems . 1–7 Accessing Preinstalled Communication Software . -
Spectrum Management Technical Handbook
NTIA TN 89-2 SPECTRUM MANAGEMENT TECHNICAL HANDBOOK TECHNICAL NOTE SERIES NTIA TECHNICAL NOTE 89-2 SPECTRUM MANAGEMENT TECHNICAL HANDBOOK l U.S. DEPARTMENT OF COMMERCE Robert A. Mosbacher, Secretary Alfred C. Sikes, Assistant Secretary for Communications and Information JULY 1989 ACKNOWLEDGEMENT NT IA acknowledges the efforts of Mark Schellhammer in the completion of Phase I of this handbook (Sections 1-3). Other portions will be added as resources are available. ABSTRACT This handbook is a compilation of the procedures, definitions, relationships and conversions essential to electromagnetic compatibility analysis. It is intended as a reference for NTIA engineers. KEY WORDS CONVERSION FACTORS COUPLING EQUATIONS DEFINITIONS ·TECHNICAL RELATIONSHIPS iii TABLE OF CONTENTS Subsection Page SECTION 1 TECHNICAL TERMS:DEFINITIONS AND NOTATION TERMS AND DEFINITIONS . .. .. 1-1 GLOSSARY OF STANDARD NOTATION . .. 1-13 SECTION 2 TECHNICAL RELATIONSHIPS AND CONVERSION FACTORS INTRODUCTION . .. .. .. 2-1 TRANSMISSION LOSS FOR RADIO LINKS . �. .. .. 2-1 Propagation Loss . .. .. .. 2-1 Transmission Loss ........................................ 2-2 Free-Space Basic Transmission Loss .......................... 2-2 Basic Transmission Loss .................................... 2-2 Loss Relative to Free-Space .................................. 2-2 System Loss . .. 2-3 ; Total Loss . .. .. 2-3 ANTENNA CHARACTERISTICS . .. 2-3 Antenna Directivity ........................................ 2-3 Antenna Gain and Efficiency .................................. 2-3 I -
Operating Manual One Piece Telephone
OPERATING MANUAL 915044V0E21J ONE PIECE TELEPHONE FEATURES OF YOUR TELEPHONE HEARING-AID COMPATIBLE HANDSET The handset on your telephone is equipped with a TONE/PULSE switch, RINGER HI LO OFF switch, MUTE, FLASH and REDIAL buttons, and a receiver that works with magnetically coupled hearing aids. ON/OFF SWITCH Press this switch to turn on the telephone to make or receive a call. When the phone is on, this button is lighted. Press it again to hang up. RINGER VOLUME CONTROL The 3 position switch is used to set ringer volume. You can select high volume (HI), low volume (LO), or you can silence the ringer (OFF). TONE/PULSE SWITCH The TONE/PULSE switch is used to set the type of dialing for your telephone to match the service from your local telephone company. PUSH BUTTON DIAL The push button dial is used to dial telephone numbers. MUTE BUTTON When the MUTE button is pressed and held, the other party cannot hear the conversation at your telephone. You can continue to listen to the other party. FLASH BUTTON The FLASH button sends a signal to the telephone service provider which tells the office that you wish to use a special feature. The results of a FLASH signal will depend on the services which are available. REDIAL BUTTON The telephone stores the last number dialed (32 digits maximum) in memory. This number may be dialed by lifting the handset and pressing the REDIAL button. The number in memory may be erased by lifting the handset and dialing any digit. HEADPHONE JACK This 3.5mm jack allows the connection of headphones or ear buds. -
Discrete Cosine Transform Based Image Fusion Techniques VPS Naidu MSDF Lab, FMCD, National Aerospace Laboratories, Bangalore, INDIA E.Mail: [email protected]
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NAL-IR Journal of Communication, Navigation and Signal Processing (January 2012) Vol. 1, No. 1, pp. 35-45 Discrete Cosine Transform based Image Fusion Techniques VPS Naidu MSDF Lab, FMCD, National Aerospace Laboratories, Bangalore, INDIA E.mail: [email protected] Abstract: Six different types of image fusion algorithms based on 1 discrete cosine transform (DCT) were developed and their , k 1 0 performance was evaluated. Fusion performance is not good while N Where (k ) 1 and using the algorithms with block size less than 8x8 and also the block 1 2 size equivalent to the image size itself. DCTe and DCTmx based , 1 k 1 N 1 1 image fusion algorithms performed well. These algorithms are very N 1 simple and might be suitable for real time applications. 1 , k 0 Keywords: DCT, Contrast measure, Image fusion 2 N 2 (k 1 ) I. INTRODUCTION 2 , 1 k 2 N 2 1 Off late, different image fusion algorithms have been developed N 2 to merge the multiple images into a single image that contain all useful information. Pixel averaging of the source images k 1 & k 2 discrete frequency variables (n1 , n 2 ) pixel index (the images to be fused) is the simplest image fusion technique and it often produces undesirable side effects in the fused image Similarly, the 2D inverse discrete cosine transform is defined including reduced contrast. To overcome this side effects many as: researchers have developed multi resolution [1-3], multi scale [4,5] and statistical signal processing [6,7] based image fusion x(n1 , n 2 ) (k 1 ) (k 2 ) N 1 N 1 techniques. -
The History of the Telephone
STUDENT VERSION THE HISTORY OF THE TELEPHONE Activity Items There are no separate items for this activity. Student Learning Objectives • I will be able to name who invented the telephone and say why that invention is important. • I will be able to explain how phones have changed over time. THE HISTORY OF THE TELEPHONE STUDENT VERSION NAME: DATE: The telephone is one of the most important inventions. It lets people talk to each other at the same time across long distances, changing the way we communicate today. Alexander Graham Bell, the inventor of the telephone CENSUS.GOV/SCHOOLS HISTORY | PAGE 1 THE HISTORY OF THE TELEPHONE STUDENT VERSION 1. Like many inventions, the telephone was likely thought of many years before it was invented, and by many people. But it wasn’t until 1876 when a man named Alexander Graham Bell, pictured on the previous page, patented the telephone and was allowed to start selling it. Can you guess what “patented” means? CENSUS.GOV/SCHOOLS HISTORY | PAGE 2 THE HISTORY OF THE TELEPHONE STUDENT VERSION 2. The picture below, from over 100 years ago, shows Alexander Graham Bell using one of his first telephones to make a call from New York to Chicago. Alexander Graham Bell making a telephone call from New York to Chicago in 1892 Why do you think it was important that someone in New York could use the telephone to talk to someone in Chicago? CENSUS.GOV/SCHOOLS HISTORY | PAGE 3 THE HISTORY OF THE TELEPHONE STUDENT VERSION 3. Today, millions of people make phone calls each day, and many people have a cellphone. -
Digital Signals
Technical Information Digital Signals 1 1 bit t Part 1 Fundamentals Technical Information Part 1: Fundamentals Part 2: Self-operated Regulators Part 3: Control Valves Part 4: Communication Part 5: Building Automation Part 6: Process Automation Should you have any further questions or suggestions, please do not hesitate to contact us: SAMSON AG Phone (+49 69) 4 00 94 67 V74 / Schulung Telefax (+49 69) 4 00 97 16 Weismüllerstraße 3 E-Mail: [email protected] D-60314 Frankfurt Internet: http://www.samson.de Part 1 ⋅ L150EN Digital Signals Range of values and discretization . 5 Bits and bytes in hexadecimal notation. 7 Digital encoding of information. 8 Advantages of digital signal processing . 10 High interference immunity. 10 Short-time and permanent storage . 11 Flexible processing . 11 Various transmission options . 11 Transmission of digital signals . 12 Bit-parallel transmission. 12 Bit-serial transmission . 12 Appendix A1: Additional Literature. 14 99/12 ⋅ SAMSON AG CONTENTS 3 Fundamentals ⋅ Digital Signals V74/ DKE ⋅ SAMSON AG 4 Part 1 ⋅ L150EN Digital Signals In electronic signal and information processing and transmission, digital technology is increasingly being used because, in various applications, digi- tal signal transmission has many advantages over analog signal transmis- sion. Numerous and very successful applications of digital technology include the continuously growing number of PCs, the communication net- work ISDN as well as the increasing use of digital control stations (Direct Di- gital Control: DDC). Unlike analog technology which uses continuous signals, digital technology continuous or encodes the information into discrete signal states (Fig. 1). When only two discrete signals states are assigned per digital signal, these signals are termed binary si- gnals. -
Alexander Graham Bell
WEEK 2 LEVEL 7 Alexander Graham Bell Alexander Graham Bell is the famous inventor of the telephone. Born in Scotland on March 3, 1847, he was the second son of Alexander and Eliza Bell. His father taught students the art of speaking clearly, or elocution, and his mother played the piano. Bell’s mother was almost deaf. His father’s career and his mother’s hearing impairment influenced the course of his career. He became a teacher of deaf people. As a child, Bell didn’t care for school, and he eventually dropped out. He did like to solve problems though. For example, when he was only 12, he invented a new farm implement. The tool removed the tiny husks from wheat grains. After the deaths of his two brothers from tuberculosis, Bell and his parents moved from Europe to Canada in 1870. They thought the climate there was healthier than in Scotland. A year later, Bell moved to the United States. He got a job teaching at the Boston School for Deaf Mutes. © 2019 Scholar Within, Inc. WEEK 2 LEVEL 7 One of his students was a 15-year-old named Mabel Hubbard. He was 10 years older than she was, but they fell in love and married in 1877. The Bells raised two daughters but lost two sons who both died as babies. Bell’s father-in-law, Gardiner Hubbard, knew Bell was interested in inventing things, so he asked him to improve the telegraph. Telegraph messages were tapped out with a machine using dots and dashes known as Morse code. -
Digital Television Systems
This page intentionally left blank Digital Television Systems Digital television is a multibillion-dollar industry with commercial systems now being deployed worldwide. In this concise yet detailed guide, you will learn about the standards that apply to fixed-line and mobile digital television, as well as the underlying principles involved, such as signal analysis, modulation techniques, and source and channel coding. The digital television standards, including the MPEG family, ATSC, DVB, ISDTV, DTMB, and ISDB, are presented toaid understanding ofnew systems in the market and reveal the variations between different systems used throughout the world. Discussions of source and channel coding then provide the essential knowledge needed for designing reliable new systems.Throughout the book the theory is supported by over 200 figures and tables, whilst an extensive glossary defines practical terminology.Additional background features, including Fourier analysis, probability and stochastic processes, tables of Fourier and Hilbert transforms, and radiofrequency tables, are presented in the book’s useful appendices. This is an ideal reference for practitioners in the field of digital television. It will alsoappeal tograduate students and researchers in electrical engineering and computer science, and can be used as a textbook for graduate courses on digital television systems. Marcelo S. Alencar is Chair Professor in the Department of Electrical Engineering, Federal University of Campina Grande, Brazil. With over 29 years of teaching and research experience, he has published eight technical books and more than 200 scientific papers. He is Founder and President of the Institute for Advanced Studies in Communications (Iecom) and has consulted for several companies and R&D agencies. -
![TELEPHONE TRAINING GUIDE] Fall 2010](https://docslib.b-cdn.net/cover/8505/telephone-training-guide-fall-2010-238505.webp)
TELEPHONE TRAINING GUIDE] Fall 2010
[TELEPHONE TRAINING GUIDE] Fall 2010 Telephone Training Guide Multi Button and Single Line Telephones Office of Information Technology, - UC Irvine 1 | Page [TELEPHONE TRAINING GUIDE] Fall 2010 Personal Profile (optional) ........................................... 10 Group Pickup (optional) ............................................... 10 Table of Contents Abbreviated Dialing (optional) ..................................... 10 Multi-Button Telephone General Description Automatic Call-Back ..................................................... 10 ....................................................................................... 3 Call Waiting .................................................................. 10 Keys and Buttons ............................................................ 3 Campus Dialing Instructions ............................ 11 Standard Preset Function Buttons .................................. 3 Emergency 911 ............................................................. 11 Sending Tones (TONE) .................................................... 4 Multi-Button Telephone Operations ................ 4 Answering Calls ............................................................... 4 Placing Calls .................................................................... 4 Transferring Calls ............................................................ 4 Inquiry Calls .................................................................... 4 Exclusive Hold ................................................................. 4 -
GLOSSARY of Telecommunications Terms List of Abbreviations for Telecommunications Terms
GLOSSARY of Telecommunications Terms List of Abbreviations for Telecommunications Terms AAL – ATM Adaptation Layer ADPCM – Adaptive Differential Pulse Code Modulation ADSL – Asymmetric Digital Subscriber Line AIN – Advanced Intelligent Network ALI – Automatic Location Information AMA - Automatic Message Accounting ANI – Automatic Number Identification ANSI –American National Standards Institute API – Applications Programming Interface ATM – Asychronous Transfer Mode BHCA – Busy Hour Call Attempts BHCC – Busy Hour Call Completions B-ISDN – Broadband Integrated Services Digital Network B-ISUP – Broadband ISDN User’s Part BLV – Busy Line Verification BNS – Billed Number Screening BRI – Basic Rate Interface CAC – Carrier Access Code CCS – Centi Call Seconds CCV – Calling Card Validation CDR – Call Detail Record CIC – Circuit Identification Code CLASS – Custom Local Area Signaling CLEC – Competitive Local Exchange Carrier CO – Central Office CPE – Customer Provided/Premise Equipment CPN – Called Party Number CTI – Computer Telephony Intergration DLC – Digital Loop Carrier System DN – Directory Number DSL – Digital Subscriber Line DSLAM – Digital Subscriber Line Access Multiplexer DSP – Digital Signal Processor DTMF – Dual Tone Multi-Frequency ESS – Electronic Switching System ETSI - European Telecommunications Standards Institute GAP – Generic Address Parameter GT – Global Title GTT – Global Title Translations HFC – Hybrid Fiber Coax IAD – Integrated Access Device IAM – Initial Address Message ICP – Integrated Communications Provider ILEC -
Guidelines on Mobile Device Forensics
NIST Special Publication 800-101 Revision 1 Guidelines on Mobile Device Forensics Rick Ayers Sam Brothers Wayne Jansen http://dx.doi.org/10.6028/NIST.SP.800-101r1 NIST Special Publication 800-101 Revision 1 Guidelines on Mobile Device Forensics Rick Ayers Software and Systems Division Information Technology Laboratory Sam Brothers U.S. Customs and Border Protection Department of Homeland Security Springfield, VA Wayne Jansen Booz-Allen-Hamilton McLean, VA http://dx.doi.org/10.6028/NIST.SP. 800-101r1 May 2014 U.S. Department of Commerce Penny Pritzker, Secretary National Institute of Standards and Technology Patrick D. Gallagher, Under Secretary of Commerce for Standards and Technology and Director Authority This publication has been developed by NIST in accordance with its statutory responsibilities under the Federal Information Security Management Act of 2002 (FISMA), 44 U.S.C. § 3541 et seq., Public Law (P.L.) 107-347. NIST is responsible for developing information security standards and guidelines, including minimum requirements for Federal information systems, but such standards and guidelines shall not apply to national security systems without the express approval of appropriate Federal officials exercising policy authority over such systems. This guideline is consistent with the requirements of the Office of Management and Budget (OMB) Circular A-130, Section 8b(3), Securing Agency Information Systems, as analyzed in Circular A- 130, Appendix IV: Analysis of Key Sections. Supplemental information is provided in Circular A- 130, Appendix III, Security of Federal Automated Information Resources. Nothing in this publication should be taken to contradict the standards and guidelines made mandatory and binding on Federal agencies by the Secretary of Commerce under statutory authority.