Explain real-time processing uses (online booking, traffic control)

1. Data Processing and Information

1.1 Data vs. Information

• Data: raw facts, figures or symbols that have no meaning until they are processed (e.g., a list of seat numbers, sensor voltage readings).
• Information: processed, organised, or interpreted data that is useful for decision‑making (e.g., “Seat 12A is available for Flight BA215”).

1.2 Quality of Information

Attribute	Why it matters
Accuracy	Correct data leads to correct decisions – no double‑booking or wrong traffic‑signal timings.
Timeliness	Information must be available when needed – the essence of real‑time processing.
Relevance	Only useful data should be presented to avoid overload of operators or users.
Completeness	Missing data can cause system failures (e.g., a traffic‑light controller without sensor input).
Consistency	All users see the same information at the same time, preventing conflicts.

1.3 Encryption, Validation & Verification

• Encryption – transforms data into a coded form so that only authorised users can read it. Example: SSL/TLS protects credit‑card details in an online‑booking portal.
• Validation – checks that entered data meets required formats or ranges. Example: a date field must be in DD/MM/YYYY format and cannot be in the past.
• Verification – confirms that data is correct and complete before it is processed. Example: a payment gateway returns a “success” code before a ticket is issued.

1.4 Processing Modes

Mode	Typical Use	Key Features
Batch Processing	Payroll, end‑of‑day sales reports	Data collected over a period, processed together; high throughput; no immediate response required.
Online (Transaction) Processing	E‑commerce, electronic funds transfer (EFT)	Immediate response to each transaction; maintains data integrity; often uses ACID‑compliant databases.
Real‑Time Processing	Online booking, traffic‑control, stock‑trading platforms	Deterministic timing, continuous operation, high reliability and redundancy; results delivered within seconds or milliseconds.

1.5 Real‑Time Processing – Key Characteristics

• Immediate response: results within seconds (online booking) or milliseconds (traffic‑signal change).
• Deterministic timing: processing must finish before a fixed deadline (e.g., a vehicle approaching an intersection).
• Continuous operation: 24 h/7 d, often without human supervision.
• High reliability & redundancy: failure can have serious safety or financial consequences.

1.6 Real‑Time Uses (Illustrative)

• Online booking systems – seat allocation, payment processing and instant confirmation.
• Traffic‑control networks – sensor data → analysis → signal change → feedback loop, all within a few seconds.

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2. Hardware and Software

2.1 Mainframe and Super‑Computer Systems

• Mainframes – large, powerful computers used for massive transaction processing (e.g., airline reservation systems, banking). Features: high I/O throughput, robust OS, extensive redundancy.
• Super‑computers – specialised for extremely fast calculations (weather modelling, scientific research). Not typically used for routine real‑time business services.

2.2 System Software

• Operating System (OS) – manages hardware resources, schedules tasks, provides services. Real‑time systems need an OS with real‑time scheduling (RTOS) such as a real‑time variant of Linux or VxWorks.
• Device Drivers – enable the OS to communicate with sensors (loop detectors, RFID readers) and actuators (traffic‑light relays, door‑lock mechanisms).

2.3 Utility Software

• Backup & recovery tools – protect booking data and traffic‑log archives.
• Antivirus & firewalls – defend real‑time services from malware and DDoS attacks.
• System‑monitoring utilities – track CPU load, memory usage, response times and generate alerts when deadlines are missed.

2.4 Application Software

• Custom (bespoke) software – written specifically for an organisation (e.g., a proprietary airline reservation system that integrates with baggage handling).
• Off‑the‑shelf software – ready‑made packages (e.g., generic ticket‑booking platforms, traffic‑management suites).

2.5 User Interfaces (UIs)

UI Type	Typical Device	Real‑Time Example
Graphical UI (GUI)	Desktop, tablet	Online booking website showing live seat availability.
Touchscreen UI	Kiosk, in‑car display	Self‑service ticket kiosk at a railway station.
Voice UI	Smart speaker, in‑car assistant	Voice‑activated traffic‑alert service (“Heavy traffic on the M25”).
Command‑line UI	Server console	System‑admin monitoring of traffic‑control servers.

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3. Monitoring and Control

3.1 Sensors and Actuators

• Sensors – convert physical conditions into electrical signals.
  • Loop detectors (inductive) – detect vehicle presence on roads.
  • Infra‑red / video cameras – count pedestrians at a station.
  • RFID readers – verify boarding passes at airport gates.
• Actuators – receive control signals and cause a physical action.
  • Relay‑controlled traffic lights.
  • Electronic door‑lock mechanisms.
  • Variable‑message signs (VMS) on highways.

3.2 Control Loops

1. Data acquisition from sensors.
2. Signal processing (often in real time).
3. Decision making (e.g., extend green‑time, allocate a seat).
4. Command sent to actuator.
5. Feedback measured again, completing the loop.

Both online‑booking and traffic‑control systems are closed‑loop; the loop time must meet a strict deadline to avoid over‑booking or traffic accidents.

3.3 Real‑Time Loop Examples

• Online booking – user request → availability check → payment gateway → confirmation → seat‑lock released.
• Traffic‑control – vehicle detector → traffic‑flow analyser → signal‑controller → changed light phase → new detector reading.

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4. Algorithms and Flowcharts

4.1 Algorithm – Real‑Time Online Booking Transaction

1. Receive booking request (user ID, resource ID, date/time).
2. Validate input format (step 4).
3. Authenticate user (username/password, token).
4. IF input invalid THEN return error and STOP.
5. LOCK the requested resource in the database.
6. Check availability:
    IF not available THEN UNLOCK resource, return “unavailable” and STOP.
7. Process payment securely (encrypt details, contact payment gateway).
8. IF payment approved THEN
       a. Record reservation,
       b. Generate confirmation number,
       c. SEND confirmation to user,
       d. UNLOCK resource.
   ELSE
       UNLOCK resource, return “payment failed”.
9. Log transaction for audit and recovery.

4.2 Flowchart – Online Booking

4.3 Flowchart – Traffic‑Control Loop

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5. e‑Security for Real‑Time Systems

5.1 Confidentiality, Integrity & Availability (CIA)

• Confidentiality – encryption of booking details, TLS for traffic‑control messages.
• Integrity – checksums, digital signatures, hash‑based message authentication codes (HMAC) to detect tampering.
• Availability – redundancy, load‑balancing, DDoS mitigation, fail‑over clusters.

5.2 Authentication & Authorisation

• Two‑factor authentication (2FA) for agents accessing reservation systems.
• Role‑Based Access Control (RBAC) for traffic‑control operators – only senior staff can change signal timings.
• OAuth/OpenID Connect for third‑party integrations (e.g., mobile‑booking apps).

5.3 Non‑Repudiation

Digital receipts, signed transaction logs and timestamped audit trails prevent users or staff from denying a booking or a signal‑change command.

5.4 Common Security Measures (Booking & Traffic)

• Secure sockets layer (SSL/TLS) for all client‑server communication.
• Input sanitisation and server‑side validation to stop injection attacks.
• Regular patching of OS and application components.
• Intrusion detection systems (IDS) monitoring abnormal traffic‑control commands.

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6. The Digital Divide

Real‑time services such as e‑booking and smart‑city traffic management can widen the gap between:

• Those with high‑speed broadband – enjoy instant booking, live traffic updates and mobile ticketing.
• Those with limited or no internet access – rely on phone or in‑person queues and may miss cheaper last‑minute offers.

Mitigation Strategies

• Public Wi‑Fi hotspots at transport hubs.
• Low‑bandwidth, mobile‑friendly interfaces (progressive web apps).
• Maintaining alternative offline channels (call centres, ticket offices).
• Community outreach and digital‑literacy programmes.

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7. Expert Systems in Real‑Time Environments

• Definition – software that uses a knowledge base and an inference engine to emulate human expert decision‑making.
• Traffic‑management example – an expert system analyses historical congestion patterns, weather forecasts and incident reports to suggest optimal signal timings before the real‑time loop even begins.
• Benefit – reduces operator workload, improves response speed during peak periods, and provides a “first‑line” decision that the real‑time controller can fine‑tune.

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8. Supporting Technologies

8.1 Spreadsheets

• Model traffic flow (e.g., calculate average vehicle arrival rates) and forecast booking demand.
• Functions such as VLOOKUP, pivot tables and Solver optimise resource allocation (seat inventory, lane timings).

8.2 Databases

Relational DBMS (MySQL, Oracle, PostgreSQL) store reservation records, seat inventories and traffic‑sensor logs.

• ACID properties prevent double‑booking and ensure consistent traffic‑signal states.
• Indexing on fields such as “flight number” or “sensor ID” enables rapid searches.
• Replication and clustering provide high availability for 24 / 7 operation.

8.3 Multimedia (Video/Audio Editing)

• Traffic‑control centres edit live CCTV footage to create short clips for incident reports.
• Booking platforms embed promotional videos or audio alerts (“Your payment is being processed”).

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9. IT in Society (A12)

• Digital currencies – Bitcoin, Ethereum; decentralised ledgers enable peer‑to‑peer payments without banks.
• Data mining – extracting patterns from large datasets (e.g., airlines predicting demand to adjust pricing).
• Social networking services – Facebook, TikTok; influence communication, marketing and privacy concerns.
• E‑learning & MOOCs – platforms such as Coursera and Khan Academy broaden access to education.
• Privacy & digital footprints – GDPR, right to be forgotten, and the impact of personal data collection.
• Digital citizenship – responsible, safe and ethical use of technology.

Key Points – A12

• Identify at least three societal impacts of IT and give a contemporary example for each.
• Explain how legislation (e.g., GDPR) influences data handling in real‑time systems.

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10. New & Emerging Technologies (A13)

Technology	Typical Application	Real‑Time Relevance
Artificial Intelligence (AI)	Chatbots, predictive maintenance	Real‑time decision making (e.g., AI‑driven traffic‑signal optimisation).
Augmented/Virtual Reality (AR/VR)	Training simulators, virtual tours	Immersive real‑time feedback for pilots or traffic‑control trainees.
Robotics	Warehouse automation, autonomous vehicles	Robots must react within strict time limits to sensor input.
Internet of Things (IoT)	Smart sensors, connected appliances	Millions of IoT devices generate real‑time data streams for traffic monitoring.
Blockchain	Secure transaction ledgers, smart contracts	Immutable records for ticket purchases; can be used in real‑time settlement.
3‑D Printing	Rapid prototyping, medical implants	On‑demand production reduces inventory, indirectly affecting booking systems.
Wearable Computing	Smart watches, health monitors	Real‑time health data can be integrated into travel‑assist services.
Quantum Computing (emerging)	Complex optimisation problems	Future potential for real‑time route optimisation.

Key Points – A13

• Provide at least one current example for each emerging technology.
• Explain how the technology could improve or disrupt real‑time processing.

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11. Communications Technology (A14)

11.1 Network Types

• LAN – Local Area Network, e.g., office wiring for booking‑system servers.
• WAN – Wide Area Network, e.g., airline’s global reservation backbone.
• PAN – Personal Area Network, e.g., Bluetooth headset for traffic‑control staff.
• MAN – Metropolitan Area Network, e.g., city‑wide traffic‑sensor network.
• Internet – Global public network used by customers to access booking portals.

11.2 Core Components

Component	Function
Router	Directs data between different networks (e.g., between airline data centre and the Internet).
Switch	Connects devices within a LAN, forwarding frames based on MAC addresses.
Hub	Simple repeater; largely obsolete but useful for teaching basic concepts.
Server	Provides services – web server for booking site, database server for transaction storage.

11.3 Cloud Computing

• IaaS – Infrastructure as a Service (e.g., Amazon EC2 for scalable booking‑system instances).
• PaaS – Platform as a Service (e.g., Google App Engine for rapid development).
• SaaS – Software as a Service (e.g., Salesforce CRM integrated with reservation data).

11.4 Transmission Media

• Twisted‑pair copper (UTP, STP) – common in LANs.
• Fibre‑optic cable – high‑speed backbone for WAN and traffic‑sensor back‑haul.
• Wireless (Wi‑Fi, Bluetooth, Zigbee) – used for mobile ticket kiosks and IoT sensors.
• Satellite – provides connectivity for remote traffic‑monitoring stations.

11.5 Protocol Stacks

• OSI Model (7 layers) – Physical, Data Link, Network, Transport, Session, Presentation, Application.
• TCP/IP Model (4 layers) – Link, Internet, Transport, Application.
• Key protocols for real‑time services: HTTP/HTTPS (booking), MQTT (IoT sensor data), RTP/RTCP (live traffic video), SIP (voice alerts).

11.6 Wireless & Mobile Technologies

• Wi‑Fi (IEEE 802.11ac/ax) – high‑speed access for passenger devices.
• Bluetooth Low Energy – communication with beacons in stations.
• Cellular (4G LTE, 5G) – provides ubiquitous connectivity for mobile booking apps and vehicle‑to‑infrastructure (V2I) traffic data.

11.7 Security in Communications

• Firewalls – filter inbound/outbound traffic to protect servers.
• VPN (Virtual Private Network) – secure remote access for airline staff.
• WPA3 – latest Wi‑Fi encryption standard.
• IPSec – encrypts data at the network layer, useful for sensor back‑haul.

Key Points – A14

• Identify the main network types and give a real‑time example for each.
• Explain the role of the OSI/TCP‑IP layers in a booking transaction.
• Discuss at least two security measures used in communications.

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12. Project Management (A15)

12.1 Project Life‑Cycle Phases

1. Initiation – define objectives, feasibility study.
2. Planning – create Gantt chart, allocate resources, risk register.
3. Execution – develop the system (coding, hardware installation).
4. Monitoring & Controlling – track progress, manage changes, quality assurance.
5. Closure – final testing, hand‑over, post‑project review.

12.2 Tools & Artefacts

• Gantt chart – visual timeline of tasks and dependencies.
• Risk register – identifies, assesses and mitigates potential problems (e.g., sensor failure).
• Stakeholder analysis – maps interest and influence of users, regulators, airlines, city council.
• Agile boards (Kanban/Scrum) – useful for incremental development of booking features.

12.3 Example – Developing a New Booking‑System Prototype

Phase	Key Activities
Initiation	Define scope (online & mobile booking), budget, success criteria.
Planning	Draft Gantt (8 weeks), assign developers, identify risk of payment‑gateway downtime.
Execution	Code front‑end UI, integrate with payment API, set up test database.
Monitoring	Daily stand‑up meetings, sprint reviews, performance testing (response < 2 s).
Closure	User acceptance testing, deployment to production, training of call‑centre staff.

Key Points – A15

• List the five project phases and one artefact associated with each.
• Contrast agile (iterative) with waterfall (sequential) approaches.

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13. System Life‑Cycle (A16)

13.1 Stages

1. Feasibility Study – technical, economic and legal viability.
2. Requirements Analysis – functional and non‑functional requirements (e.g., response time < 1 s for seat allocation).
3. System Design – logical (data model, process flow) and physical (hardware, network topology).
4. Implementation – coding, hardware installation, configuration.
5. Testing – unit, integration, system, acceptance, performance.
6. Deployment – migration, user training, go‑live.
7. Maintenance – corrective, adaptive, perfective, preventive.
8. Evaluation – post‑implementation review against objectives.

13.2 Real‑Time Considerations

• During design, specify deterministic timing requirements (e.g., “signal change must occur within 3 s of sensor trigger”).
• Testing must include load‑testing to ensure response times under peak traffic.
• Maintenance contracts often include 24 / 7 support and rapid‑recovery SLAs.

Key Points – A16

• Provide a brief description of each life‑cycle stage.
• Explain why testing and maintenance are critical for real‑time systems.

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14. Systems Development Methodologies (A17)

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Methodology	Key Features	Suitability for Real‑Time Projects
Waterfall	Sequential phases, heavy documentation.	Useful when requirements are stable (e.g., government traffic‑control upgrades).
Prototyping	Quick mock‑ups, user feedback early.	Helps refine UI for booking portals before full implementation.
Rapid Application Development (RAD)	Iterative builds, reusable components.	Accelerates development of mobile booking apps.
Agile (Scrum/Kanban)