Digital Communication and Switching Past Lecture Notes PDF

EETE 4220 Digital Communication and Switching Semester I AY 2024-25 Class Lecture -9 Outcome #10 & #11- Traffic Engineering & Modern Local Access Techniques Course Le...

EETE 4220 Digital Communication and Switching Semester I AY 2024-25 Class Lecture -9 Outcome #10 & #11- Traffic Engineering & Modern Local Access Techniques Course Lecturer :Lenin Joseph (LJ) E&E Section. Dept. of Engineering. ACT Dec 24, 2024 1 OUTCOME #10 & #11 10. Understand about Traffic Engineering – Erlang’s formula, Traffic Load, GoS 11. Describe the modern local access techniques – xDSL, WLL. EETE 4220 Digital Communication & Switching -E&E Section. Dept. of Engine Dec 24, 2 ering. ACT 2024 INTRODUCTION TO TRAFFIC ENGINEERING  Traffic engineering is a method of optimizing the performance of a telecommunications network by dynamically analyzing, predicting and regulating the behavior of data transmitted over that network. TI - 1011 3 TRAFFIC ENGINEERING Traffic engineering is also known as teletraffic engineering and traffic management. The techniques of traffic engineering can be applied to networks of all kinds, including the PSTN (public switched telephone network), LANs (local area networks), WANs (wide area networks), cellular telephone networks, proprietary business and the Internet. Overview The theory of traffic engineering was originally conceived by A.K. Erlang, a Danish mathematician who developed methods of signal traffic measurement in the early 1900s. In a telephone network, traffic is measured in call seconds (CCS) or erlangs. One CCS is equal to 100 seconds of telephone time. One erlang is equal to one hour or 36 CCS of telephone time Requirement When message queues become unacceptably long or A major objective of traffic the frequency of busy signals engineering is to minimize or becomes unacceptably high, eliminate high-loss situations. the network is said to be in a high-loss condition. Balance the QoS Another goal of traffic engineering is to balance the QoS (Quality of Service) against the cost of operating and maintaining the network. DIGITAL TELEPHONY and BROADBAND ACCESS TECHNOLOGIES  Integrated Services Digital Network (ISDN)  Internet Protocol (IP) Telephony  xDSL  Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH)  Asynchronous Transfer Mode (ATM) and Frame Relay  Cable Internet access  Fiber to the home (FFTH) EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 9 er 24, 2 024 Integrated Services Digital Network (ISDN)  Integrated Services for Digital Network (ISDN) is a set of communication standards for simultaneous digital transmission of voice, video, data, and other network services over the traditional circuits of the public switched telephone network.  ISDN is a circuit-switched telephone network system, which also provides access to packet switched networks  Integrated services refer to ISDN's ability to deliver at minimum two simultaneous connections, in any combination of data, voice, video, and fax, over a single line EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 10 er 24, 2 024 Internet Protocol (IP) Telephony  Commonly known as Voice over IP  The term Internet telephony specifically refers to the provisioning of communications services (voice, fax, SMS, voice-messaging) over the public Internet, rather than via the public switched telephone network (PSTN).  Telephone system for Computer Networks is knows as Voice over IP. EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 11 er 24, 2 024 Internet Protocol (IP) Telephony  It includes internal call, message forwarding, speed dialing, voice mail and access to the local PSTN.  The steps and principles involved in originating VoIP telephone calls are similar to traditional digital telephony and involve signaling, channel setup, digitization of the analog voice signals, and encoding.  Instead of being transmitted over a circuit-switched network, however, the digital information is packetized, and transmission occurs as IP packets over a packet-switched network.  IP telephony uses an Internet connection and hardware IP Phones, analog telephone adapters, or softphone computer applications to transmit conversations encoded as data packets. EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 12 er 24, 2 024 xDSL  DSL originally stood for "digital subscriber loop".  xDSL is a generic representation of the various DSL technologies that are available. EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 13 er 24, 2 024 xDSL It uses existing copper telephone lines for carrying the data. Copper telephone lines can carry high-speed data over limited distances, and the DSL technologies use this trait to provide a high- data-rate connection. Digital Subscriber Line service provides a connection to the Internet through the telephone network. DSL uses the high frequencies, while the low (audible) frequencies of the line are left free for regular telephone communication. These frequency bands are subsequently separated by filters installed at the customer's premises. DSL services uses filtering techniques to enable the transport of data and voice traffic on the same cable. E&E Section. Dept. of Engineering. ACT Dec 24, 14 2024 ADSL & SDSL ADSL (Asymmetric DSL) is a telephone local loop that combines analog telephone service with data communication wherein the downstream data rate is greater than the upstream rate. With a Symmetric Digital Subscriber Line (SDSL), the downstream and upstream data rates are equal. EETE 3270 Data Communications E&E Section. Dept. of Engineering. ACT Decemb 15 er 24, 2 024 VDSL Very-high-bit-rate digital subscriber line (VDSL or VHDSL, ITU G.993.1) is a digital subscriber line (DSL) standard approved in 2001 VDSL is capable of supporting applications such as high-definition television, as well as telephone services (voice over IP) and general Internet access, over a single physical connection. E&E Section. Dept. of Engineering. ACT Dec 24, 16 2024 REFERENCES Text Book Frenzel, L., Principles of Electronic Communication Systems, 3rd Ed. McGrawHill, 2008 Book References Sklar, Benard, “Digital Communications: Fundamentals and Application”, Prentice Hall, USA, 2001 Glover, Ian A / Grant, Peter M, “ Digital Communications”, Prentice Hall, UK, 2004 Proakis,John G,“ Digital Communications”, McGraw Hill Inc, USA, 2000 Wesolowski,Krzysztof, “Introduction to Digital Communication Systems”,2009 Web References\ e-library(s) https://ebookcentral.proquest.com/lib/momp/detail.action?docID=3011330 571, CD/DVD, Electronic Communication Systems: A complete Course, ACT Store THANK YOU