Unit 6 · Session 4
Web Pages, E-Commerce, Smart City, Intranet and Extranet
Today's focus
- Static vs Dynamic Web Pages
- Smart City
- Intranet & Extranet
🎯 Learning Objectives
By the end of this session, you will be able to:
- ✅ Differentiate between static and dynamic web pages.
- ✅ Define a smart city and the core technologies that enable it.
- ✅ Give examples of smart city applications in action.
- ✅ Explain intranets and extranets and how they differ from the public Internet.
Static vs Dynamic Web Pages
Static Web Pages
A web page delivered to the user exactly as it is stored on the server.
- Technology: Plain HTML and CSS.
- Speed: Loads instantly with no processing required.
- Limitations: Content is fixed and must be manually updated by editing HTML files.
Dynamic Web Pages
A web page whose content is generated "on the fly" by the server.
- Technology: Server scripts (PHP, Node.js) and Databases (MySQL).
- Personalization: Can show different content to different users (e.g., social media feeds).
- Management: Can be updated via a CMS (like WordPress) without touching code.
Key Differences
| Feature | Static | Dynamic |
|---|---|---|
| Content | Fixed | Changes based on user/time |
| Database | None | Heavily used |
| Complexity | Low | High |
🧪 Activity: Static or Dynamic?
Decide whether each page is static or dynamic, and give your reason.
1. A restaurant's one-page site with its address and menu. Static: the same for everyone, and rarely changes
2. Your Facebook news feed. Dynamic: built for you, every time
3. Daraz search results for "headphones". Dynamic: pulled from a product database
4. A designer's portfolio page. Static
5. Checking your exam result by entering your symbol number. Dynamic: looked up in a database
6. A Wikipedia article. Dynamic: it looks fixed, but it's built from a database and anyone can edit it
⚙️ What Happens When a Dynamic Page Loads?
You log in to Daraz and see "Hi, Sita" with your recent orders.
- Your browser sends a request, including who you are (your login).
- The server runs a script (for example PHP or Node.js).
- The script asks the database: "What are Sita's name, orders and recommendations?"
- The script builds a fresh HTML page from the answers.
- The server sends that page back. The next user gets a different one.
Many modern sites mix both. This course website is static: its pages are built in advance with a tool called Jekyll, so they load fast and need no database.
🛒 E-Commerce: Buying and Selling on the Web
E-commerce means buying and selling goods or services over the Internet. It is classified by who sells to whom.
| Type | Who sells to whom | Example |
|---|---|---|
| B2C | Business → Consumer | Daraz, Netflix |
| B2B | Business → Business | Alibaba.com wholesale orders |
| C2C | Consumer → Consumer | Hamrobazar, eBay |
| C2B | Consumer → Business | Freelancers selling designs or photos to companies |
| G2C | Government → Citizen | Paying tax online on the IRD site |
🔗 How an Online Order Works
- Browse: dynamic pages show products, prices and stock from a database.
- Cart and checkout: the site saves your choices and address.
- Payment: a payment gateway (a card, eSewa or Khalti) confirms the money. Cash on delivery is still very common in Nepal.
- Fulfilment: the order goes to a warehouse or seller to be picked and packed.
- Delivery and tracking: a courier delivers it, with status updates sent to your phone.
- After-sales: reviews, returns and refunds.
The website is only the front door. Behind it sit databases, payment systems, warehouses and couriers, all linked by information systems.
Last-mile delivery: Pathao rider, Dhaka
🌏 Global Case: Singles' Day, the World's Biggest Shopping Day
- Every 11 November (11.11), Chinese shoppers flood Alibaba's online stores.
- In 2019, Alibaba recorded about US$38 billion of sales in 24 hours.
- At the peak, its systems handled about 544,000 orders per second.
Think: A static page could never do this. What must the servers, databases and payment systems handle in that one second? What happens to a small shop's website if 10,000 people visit at once?
🎬 Watch: Parcel-Sorting Robots
🧮 Worked Example: Is Selling Online Worth It?
Illustrative figures. A Kathmandu shop sells a pashmina shawl online for Rs 4,000.
Per shawl
- Cost of the shawl: Rs 2,400
- Marketplace commission (10%): Rs 400
- Payment fee (2%): Rs 80
- Delivery: Rs 150
- Profit: Rs 970
Per month
- 120 orders × Rs 970 = Rs 1,16,400
- Online ads: − Rs 20,000
- Monthly profit: Rs 96,400
Your turn: If returns cost the shop Rs 300 each and 10% of orders come back, what's the new monthly profit? (12 returns × Rs 300 = Rs 3,600, so Rs 92,800)
Smart City
What is a Smart City? 🏙️
An urban area that uses IoT sensors to collect data and uses insights to manage assets, resources, and services efficiently.
- Aims to improve quality of life and sustainability.
- Relies on data analytics and connectivity.
Core Technologies 🔌
- Internet of Things (IoT): Sensors embedded in infrastructure.
- Big Data Analytics: Processing massive streams of urban data.
- Artificial Intelligence: Automating city responses based on real-time data.
- Cloud Computing: Storing and processing the data securely.
Smart Applications in Action
Traffic
Sensors adjusting traffic lights in real-time to reduce jams.
Waste
Garbage bins alerting collectors only when full.
Energy
Smart grids balancing power loads efficiently.
Safety
Connected streetlights turning on when pedestrians approach.
Bigbelly: solar smart bin
Traffic near Dharahara, Kathmandu
🌆 Global Cases: Singapore and Songdo
🇸🇬 Singapore
- Since 1998, Electronic Road Pricing has charged cars automatically as they pass under gantries on busy roads.
- Prices change with the time of day and traffic, so drivers spread their trips out.
- In 2014 the government launched its Smart Nation plan to link sensors, data and public services.
🇰🇷 Songdo, South Korea
- A district built from scratch near Incheon as a planned smart city.
- Household rubbish is sucked through underground pipes to a central plant, so there are no rubbish trucks on the streets.
- Sensors monitor traffic, energy use and the environment.
Smart cities don't start with gadgets. They start with a problem, such as traffic or waste, and use data to manage it.
🎬 Watch: Singapore's Electronic Road Pricing
🇳🇵 Activity: Design a Smart Kathmandu
In groups of 3–4, pick one problem and design a smart solution in 3 minutes.
Pick a problem
- 🚗 Traffic jams on the Ring Road
- 🗑️ Rubbish piling up on streets
- 💧 Long queues for drinking water
- 🌫️ Winter air pollution
- 🚌 Not knowing when the next bus comes
Answer four questions
- What data do you need?
- Which sensors or apps collect it?
- Who acts on it, and how?
- What is one risk (cost, privacy, power cuts)?
Two groups share their design in 30 seconds each.
Intranet & Extranet
What is an Intranet? 🏢
A private network contained within an enterprise used to securely share company information and resources among employees.
- Functions like the Internet but is closed off to the public.
- Uses firewalls for security.
- Uses: Employee directories, internal memos, HR portals.
What is an Extranet? 🤝
An intranet that can be partially accessed by authorized outside users.
- Securely shares business info with partners, vendors, or suppliers.
- Requires authentication (VPNs, secure logins).
- Uses: Supply chain management, client portals.
Comparing the Networks
| Feature | Internet | Intranet | Extranet |
|---|---|---|---|
| Access | Public | Internal Employees | Trusted Partners |
| Security Level | Low | High | High |
🧪 Activity: Internet, Intranet or Extranet?
1. A bank's leave-request portal that only staff can open. Intranet
2. A supplier logs in to a supermarket chain's portal to check stock and send invoices. Extranet
3. Daraz's public shopping website. Internet
4. A company's internal wiki of procedures and policies. Intranet
5. A car maker lets its dealers check order and delivery status. Extranet
6. A law firm's portal where clients log in to download their case documents. Extranet
🏬 Case Study: Walmart's Supplier Extranet
- Since the early 1990s, Walmart has run Retail Link, a secure system that its suppliers log in to.
- A supplier such as a toothpaste maker can see how much of its product sold in each store, and how much is left on the shelves.
- Suppliers use this to plan production and restock shelves before they run empty, so Walmart holds less stock and has fewer empty shelves.
- Outsiders see only their own products. Walmart's other data stays private, which is exactly what makes it an extranet.
Think: How could a Nepali supermarket chain use a supplier extranet with its dairy or bakery suppliers?
🎯 Key Takeaways
- Static pages are the same for everyone. Dynamic pages are built on request from a database.
- E-commerce (B2C, B2B, C2C, C2B, G2C) depends on dynamic sites plus payment, warehouse and delivery systems.
- A smart city uses sensors and data to solve real urban problems, but raises questions about cost and privacy.
- An intranet is for employees only. An extranet lets trusted outsiders in to a limited part of it.
💬 Discussion Questions
- A small hotel in Pokhara wants a website. Should it be static or dynamic? What would change your answer?
- Why is cash on delivery still so common in Nepal? What would make more people pay online?
- Which smart city application would make the biggest difference to daily life in your town, and what is stopping it?
- A company gives a supplier access to its extranet. What could go wrong, and how should the company protect itself?
Exam Practice 📝
Short answer
- Differentiate between static and dynamic web pages with examples.
- How does an extranet reduce transaction costs in modern supply chain management?
- Distinguish between B2B and B2C e-commerce with specific examples.
- Explain client-side and server-side scripting.
Revise the answers in the full notes linked on the last slide.
Image & Video Credits
Images
- Static/dynamic request diagrams: based on "Scheme static page en.svg" and "Scheme dynamic page en.svg" by Ggia, CC BY-SA 3.0, via Wikimedia Commons (white-backed composite for this deck)
- "ERP gantry on the BKE.jpg" by Jnzl, CC BY 2.0, via Wikimedia Commons
- "Big Belly Solar Compactor - geograph.org.uk - 2615687.jpg" by M J Richardson, CC BY-SA 2.0, via Wikimedia Commons
- "Dharahara and Traffic.jpg" by Gaurav Dhwaj Khadka, CC BY-SA 4.0, via Wikimedia Commons
- "Pathao rider from dhaka.jpg" by Aashaa, CC BY-SA 3.0, via Wikimedia Commons
- VPN overview: based on "VPN overview-en.svg" by Michel Bakni, CC BY-SA 4.0, via Wikimedia Commons (white-backed PNG for this deck)
- "Walmart box-trailer semi.jpg" by Eric Polk, CC BY-SA 4.0, via Wikimedia Commons
Videos (YouTube)
- CGTN, "Watch an army of robots efficiently sorting hundreds of parcels per hour" (0:10 to 1:30), YouTube jwu9SX3YPSk
- KnowHub, "How Singapore Mastered Traffic Management: The Singapore Model!" (1:08 to 2:20), YouTube bXOWvWyrb4g
Thank You
Questions before we wrap this hour?
Next: Unit 7 · Session 1 — Multimedia Systems and Elements
📖 Read the full notes: Static and Dynamic Web Pages · Intranet, Extranet, Censorship, and Privacy Issues · E-Commerce, E-Governance, and Smart Cities
📖 Related chapter notes
Read first, then revise with this deck: