1. ADG 1 Fall 2013 Review A slide to a chapter summary of the material covered (based on the 8/e book)

2. ADG 2 C1. Data Communications and Networking Overview The 3 (or 5) entity general communication model Actual data communications is more complicated –Transmission system utilization, interface, signal generation, synchronization, exchange management, error detection and correction, flow control, addressing, routing, recovery, message formatting, security, network management Networking –LANs –MANs –WANs circuit switching, packet switching –frame relay, cell relay

3. ADG 3 C2. Protocol Architecture A simple (quite general) protocol architecture –Protocols: syntax, timing, semantics Layering combats complexity Open System Interconnection (OSI) –7 layers –Standardisation framework –Service Primitives, and Parameters The TCP/IP protocol architecture –5 layers –The “industry” standard

4. ADG 4 C3. Data transmission Terminology –Frequency, spectrum, bandwidth etc Any signal can be expressed as an infinite number of sine waves (frequency components). –Remember it is only the odd ones (1, 3, 5, 7….) Relationship between data rate and bandwidth –The higher the data rate the higher the required bandwidth –The higher the bandwidth the greater data rate can be achieved Transmission impairments (attenuation, delay distortion, noise) Channel capacity (Nyquist, Shannon)

5. ADG 5 C4. Transmission Media Guided media (description, characteristics, categories) (3) Wireless transmission technologies (3) –Dish antenna, Antenna gain Wireless propagation (3) Wireless (line-of-sight) impairments (4)

6. ADG 6 C5. Signal Encoding Techniques Digital & Analogue Data –to Digital & Analogue Signals D-data  A-signal(3) D-data  D-signal(3, 6, scrambling) A-data  D-signal(2) A-data  A-signal(3)

7. ADG 7 C6. Digital Data Communication Techniques Transmission approaches –Synchronous –Asynchronous Errors, types Error detection Error correction

8. ADG 8 C7. Data Link Control Protocols Flow control (SAW, SW) Error control (ARQ and its mechanisms) HDLC protocol –Basics (types of stations, configuration and modes) –Frame types and structure –Operation

9. ADG 9 C8. Multiplexing Utilising a single line to relay multiple connections Frequency Division Time Division Statistical Time Division (relies on non frequent use) ADSL –Separates the 1MHz in 3 regions –FDM within upload and download

10. ADG 10 C14. Cellular Wireless Networks Not covered fully (first 14 slides) Cellular network organisation –Cells –Frequency reuse –Increasing the capacity Operation of a cellular systems –Base station –Cells –MTSO

11. ADG 11 C17. Wireless Networks Single and multi cell LANs Applications (nomadic, adhoc, cross building, lan extension) Technologies –IR, Spread spectrum, Narrow band microwave

12. ADG 12 C15. LAN Overview LAN applications (high speed, backbone, storage area networks, personal, backend) Topologies (ring, star, bus, tree) IEEE 802 reference model –LLC and MAC Medium Access Control –Central vs distributed –Synchronous vs asynchronous Asynchronous –Round robin, reservation, contention Bridges (only basic functionality)

13. ADG 13 Finally (the exam) 40 Multiple choice questions –I might increase the number, I’ll let you know on my website Wednesday 15/01/2014 This room (216) Between 09:00 and 11:30 Bring (Yourself (on time)) –Your stationary –A watch (silent mobiles are allowed) –A dictionary (if you need one) –A bottle of water or drink (only if it has a cap, no open glasses and such)