Lecture1- Data Communications, Data Networking, and the Internet.pdf

CSS331 Fundamentals of Data Communications Asst.Prof.Dr.Sasiporn Usanavasin 1  How to get materials CSS331 Google Classroom & Line Group – Section 1 (Tue, 9:00-12:00) : – Section 2 (Wed, 9:00-12:00): ...

CSS331 Fundamentals of Data Communications Asst.Prof.Dr.Sasiporn Usanavasin 1  How to get materials CSS331 Google Classroom & Line Group – Section 1 (Tue, 9:00-12:00) : – Section 2 (Wed, 9:00-12:00):  Course Evaluation Attendance and Review Exercises 10% ▪ Attendance check (randomly check) Assignments (individual & group) 30% ▪ 2 Presentations Midterm Exam 30% Final Exam 30% 3 DO NOT CHEAT CHEATING = F 4  Text Books [Main Text Book] Data and Computer Communications by William Stallings [Additional Reading] Data Communications and Networking By Behrouz A.Forouzan 5  Class Schedule Section 1 (Tuesday 9:00-12:00 Room 3509), Section 2 (Wed 9:00-12:00 Room 3509) Week Sec 1 Schedule Sec 2 Schedule Topic Introduction to Data Communications, Data Networking, and the Internet 1 13-Aug-24 14-Aug-24 Protocol Architectures Group Presentation Assignments 2 20-Aug-24 21-Aug-24 Data Transmission and Transmission Media 3 27-Aug-24 28-Aug-24 Signal Encoding Technique 4 3-Sep-24 4-Sep-24 Error Detection and Correction Techniques 5 10-Sep-24 11-Sep-24 Review Exercises 6 17-Sep-24 18-Sep-24 Group Presentation#1 7 24-Sep-24 25-Sep-24 No Class (Reading Week for Midterm Exam) 30 Sep 2024 8 Midterm Exam (9:00-11:00) Data Link Control 9 8-Oct-24 9-Oct-24 Multiplexing Techniques WAN Technologies and Protocols 10 15-Oct-24 16-Oct-24 ATM 11 22-Oct-24 23-Oct-24 IP Address and Subnet and Rounting Algorithms 12 29-Oct-24 30-Oct-24 Review Exercises Email 13 5-Nov-24 6-Nov-24 Network Topology 14 12-Nov-24 13-Nov-24 Group Presentation#2 15 19-Nov-24 20-Nov-24 Review Exercises 16 26-Nov-24 27-Nov-24 NO Class (Reading Week for Final Exam) 2 Dec 2024 Final Exam 17 (9:00-12:00) 6  Chapter 1 Data Communications, Data Networks, and the Internet 7 1.DATA COMMUNICATIONS The term telecommunication means communication at a distance. The word data refers to information presented in whatever form is agreed upon by the parties creating and using the data. Data communications are the exchange of data between two devices via some form of transmission medium such as a wire cable. 1.8 Effective Characteristics of Data Communication Delivery (intended receiver) Accuracy (unchanged data) Timeliness Jitter (uneven delay in audio/video streaming) 1.9 10 Five components of data communication 1.11 Data flow (simplex, half-duplex, and full-duplex) 1.12  Data Communications Trends ⚫ traffic growth at a high & steady rate ⚫ development of new services ⚫ advances in technology ⚫ Internet of things Significant change in requirements ⚫ emergence of high-speed LANs ⚫ corporate WAN needs ⚫ digital electronics https://www.statista.com/statistics/553730/number-of-internet-users-thailand/ 13 14  Thailand Broadband Speed https://www.bangkokpost.com/business/2054991/thailand-tops-internet-speed-testing 15  Notable Trends Trend toward faster and cheaper, in Today’s networks are more “intelligent” both computing and communication Differing levels of quality of service (QoS) More powerful computers supporting Variety of customizable services in the areas of more demanding applications network management and security The increasing use of optical fiber and high-speed wireless has brought transmission prices down and greatly increased capacity The Internet, the Web, and associated Mobility applications have emerged as iPhone, Droid, and iPad have become drivers of the dominant features for both business evolution of business networks and their use and personal network landscapes Enterprise applications are now routinely delivered “Everything over IP” on mobile devices Intranets and extranets are being used Cloud computing is being embraced to isolate proprietary information Automated Vehicle Internet of Things (IoT) 16 Changes in Networking Technology * Emergence of high-speed networks * Corporate WAN needs * Digital electronics 17  Emergence of High-Speed LANs Personal computers and microcomputer workstations have become an essential tool for office workers Explosive growth of speed and computing power of personal computers, mobile Two significant devices trends altered the requirements of the LANs have been recognized as a LAN viable and essential computing platform Examples of requirements that call for higher-speed LANs: ⚫ Centralized server farms ⚫ Power workgroups ⚫ High-speed local backbone 18 Corporate Wide Area Networking Needs Changes in Growing use of telecommuting corporate Nature of the application structure has changed data traffic patterns are Intranet computing driving the creation of More reliance on personal computers, workstations, and servers high-speed More data-intensive applications WANs Every organizations require access to the Internet Traffic patterns have become more unpredictable Average traffic load has risen More data is transported off premises and into the wide area 19  Digital Electronics The rapid conversion of consumer electronics to digital technology is having an impact on both the Internet and corporate intranets – Image and video traffic carried by networks is dramatically increasing Because of their huge storage capacity digital versatile disks (DVDs) are being incorporated into Web sites Digital camcorders have made it easier to make digital video files to be placed on corporate and Internet Web sites 20  Key Communications Tasks Transmission system utilization Addressing Interfacing Routing Signal generation Recovery Synchronization Message formatting Exchange management Security Error detection and correction Network management Flow control 21  A Communications Model generate transform & decode & convert process data data encode data data into ex. transform bit acceptable format stream into ex. Convert analog signal analog signal into bit stream 22 Data Communications Model 23  Transmission Medium Selection is a basic choice internal use entirely up to business long-distance links made by carrier Rapid technology advances change mix fiber optic wireless Transmission costs still high Hence interest in efficiency improvements 24 2. NETWORKS A network is a set of devices (often referred to as nodes) connected by communication links. A node can be a computer, printer, or any other device capable of sending and/or receiving data generated by other nodes on the network. 1.25 Network Criteria Performance: transit time (device to device) response time (enquiry to response) throughput delay Reliability Security 1.26  Networking growth of number & power of computers is driving need for interconnection also seeing rapid integration of voice, data, image & video technologies two broad categories of communications networks: Local Area Network (LAN) Wide Area Network (WAN) 27  Wide Area Networks (WAN) span a large geographical area require crossing of public rights-of-way and rely in part on common carrier circuits WAN uses technologies such as: ⚫Circuit switching ⚫Packet switching ⚫Frame relay ⚫Asynchronous Transfer Mode (ATM) 28  Circuit Switching uses a dedicated communications path established for duration of conversation comprising a sequence of physical links with a dedicated logical channel ⚫eg. telephone network 29  Packet Switching Data is sent in a sequence of small chunks, called packets Packets passed from node to node between source and destination This is used for terminal to computer and computer to computer communications Switching Node 30 31  Frame Relay Packet switching systems have large overheads to compensate for errors Modern systems are more reliable so errors can be caught in the end system Frame Relay provides higher speeds with most error control overhead removed Frame Relay uses packet switching methodology on virtual circuit It is an implementation of a virtual circuit packet switching. 32 33  Asynchronous Transfer Mode (ATM) It is evolution of frame relay ATM uses fixed-length packets, called cells Similar to Frame Relay, ATM provides little overhead for error control (less than Frame Relay) ATM can work in the range of 10s and 100s of 10Mbps and Gbps range Constant data rate using packet switching technique with multiple virtual circuits 34  Local Area Networks (LAN) smaller scope Building or small campus usually owned by same organization as attached devices data rates much higher switched LANs, eg Ethernet wireless LANs 35  Metropolitan Area Networks (MAN) middle ground between LAN and WAN private or public network high speed large area 36  The Internet Internet evolved from ARPANET developed in 1969 by the Advanced Research Projects Agency (ARPA) of the U.S. Department of Defense It was first operational packet network ⚫It was applied to tactical radio & satellite nets ⚫It had a need for interoperability, which led to standardized TCP/IP protocols 37 Internet Elements 38 Internet Architecture 39 Example Configuration 40  Summary introduced data communications needs communications model defined data communications overview of networks introduce Internet 41