Fall 2013 Review
A slide to a chapter summary of the
material covered
(based on the 8/e book)
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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
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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
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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)
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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)
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C5. Signal Encoding Techniques
• Digital & Analogue Data
– to Digital & Analogue Signals
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D-dataA-signal(3)
D-dataD-signal(3, 6, scrambling)
A-dataD-signal(2)
A-dataA-signal(3)
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C6. Digital Data Communication
Techniques
• Transmission approaches
– Synchronous
– Asynchronous
• Errors, types
• Error detection
• Error correction
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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
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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
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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
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C17. Wireless Networks
• Single and multi cell LANs
• Applications (nomadic, adhoc, cross
building, lan extension)
• Technologies
– IR, Spread spectrum, Narrow band microwave
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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)
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Finally (the exam)
• 40 Multiple choice questions
– I might increase the number, I’ll let you know on my website
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Wednesday 15/01/2014
This room (216)
Between 09:00 and 11:30
Bring (Yourself (on time))
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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)
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