The Internet is an interconnected network of thousands of networks and millions of computers (sometimes called host computers or nodes) linking businesses, educational institutions, government agencies, and individuals.

Learning Objectives

By the end of this chapter, you will be able to:

  • Describe the three phases in the evolution of the Internet.
  • Explain packet switching and compare it with circuit switching.
  • Describe the four layers of the TCP/IP model and the role of IP addresses.
  • Explain client/server computing and how cloud computing extends it.
  • Outline the development and current state of the Internet in Nepal.

1. Evolution of the Internet: Three Phases

The history of the Internet can be divided into three distinct stages:

  1. The Innovation Phase (1961–1974): The fundamental building blocks—packet switching, TCP/IP, and the client/server model—were conceptualized and tested. The focus was on military and academic communication (ARPANET).
  2. The Institutionalization Phase (1975–1995): Large institutions like the Department of Defense (DoD) and the National Science Foundation (NSF) provided funding and legitimacy. The Internet was used primarily for scientific and academic purposes.
  3. The Commercialization Phase (1995–Present): With the privatization of the backbone and the emergence of the World Wide Web, the Internet transformed into a global commercial marketplace.

2. Key Technology Concepts

The Internet’s reliability and scalability rest on three core technologies:

A. Packet Switching

Unlike traditional circuit switching (used in old telephone systems), Packet Switching breaks digital messages into units called packets, sends them along different communication paths as they become available, and then reassembles them at their destination.

  • Benefit: It makes much more efficient use of a network’s communications capacity than circuit switching.
flowchart LR
  Msg[Digital Message] --> Split[Split into Packets]
  Split --> R1[Route A]
  Split --> R2[Route B]
  Split --> R3[Route C]
  R1 --> Asm[Reassemble at Destination]
  R2 --> Asm
  R3 --> Asm
  Asm --> Dest[Delivered Message]

Figure 1: Packet switching path from sender to receiver

B. TCP/IP (The 4-Layer Model)

The TCP/IP Protocol Suite is the universal “language” of the Internet. It consists of four layers:

  1. Network Interface Layer: Handles the physical connection (Ethernet, Wi-Fi).
  2. Internet Layer: Routes packets using IP addresses (Internet Protocol).
  3. Transport Layer: Ensures packets are delivered reliably and in order (Transmission Control Protocol).
  4. Application Layer: Provides services to users (HTTP, FTP, SMTP).

Note on Addressing: Every device on the Internet has a unique IP Address. Due to the exhaustion of 32-bit addresses (IPv4), the world is transitioning to 128-bit IPv6 addresses.

C. Client/Server Computing

In this model, powerful “Servers” provide resources (websites, databases), and “Clients” (Laptops, Smartphones) request them. In the modern era, Mobile Computing has become the dominant client platform.

D. Circuit Switching vs Packet Switching

Feature Circuit switching (old telephone) Packet switching (Internet)
Connection A dedicated path is reserved for the call No reserved path; packets share all links
Use of capacity Wasted during silences Efficient; idle capacity used by others
If a link fails The call drops Packets are rerouted around the failure
Cost High per connection Low; many users share the network

This efficiency and resilience is why the Internet could grow cheaply enough to carry global e-commerce.

E. From Client/Server to Cloud Computing

Early e-commerce firms bought and ran their own servers. Today most use cloud computing: they rent computing power, storage, and software from providers such as Amazon Web Services, Microsoft Azure, or Google Cloud, and pay only for what they use. A Nepali online shop can start on a cloud server for a small monthly fee and add capacity during the Dashain sale, then reduce it afterwards. The client/server model still applies; the servers simply belong to someone else.

The Internet Landscape in Nepal

The history of the Internet in Nepal is a story of rapid transition from dial-up to high-speed fiber.

1. Historical Context

  • 1994/1995: The first commercial Internet connection was established by Mercantile Office Systems via a data link to Pune, India.
  • Early 2000s: Introduction of VSAT (satellite) and ADSL (copper-based) technology by Nepal Telecom.
  • The Fiber Revolution (2015-Present): ISPs like Worldlink and Vianet disrupted the market with FTTH (Fiber to the Home), making high-speed streaming and e-commerce feasible.

2. Current Challenges & Opportunities

Despite high penetration, several hurdles remain:

  • Cost vs. Quality: While mobile data is relatively affordable, fiber consistency in rural areas remains a challenge.
  • Digital Divide: Significant gap between urban centers (Kathmandu, Pokhara) and remote Himalayan regions.
  • Cybersecurity Awareness: As more Nepalis join the digital economy (eSewa, Daraz), literacy regarding phishing and online fraud is critical.

3. Key Players

  • Nepal Telecom (NT): The state-owned incumbent providing both mobile and fixed lines.
  • Ncell: The major private mobile network operator.
  • ISPs: Worldlink (the largest), Vianet, DishHome, and ClassicTech.

Discussion Questions

  1. How does packet switching differ from circuit switching, and why is this critical for e-commerce?
  2. Explain the role of the DNS (Domain Name System) in navigating the Internet.
  3. Research the current status of 5G rollout in Nepal. What challenges is Nepal Telecom facing in its implementation?

Summary

The Internet is a network of networks that grew through innovation, institutionalisation, and commercialisation phases. Three technologies made it possible: packet switching, which breaks data into packets that share links efficiently; the TCP/IP protocol suite, which addresses, routes, and reliably delivers those packets; and client/server computing, now extended by mobile clients and cloud servers. In Nepal, the Internet moved from a single dial-up link in the mid-1990s to widespread fibre and mobile broadband, although rural access and security awareness remain challenges.

Key Takeaways

  • The Internet developed in three phases: innovation, institutionalisation, and commercialisation.
  • Packet switching is cheaper and more resilient than circuit switching.
  • TCP/IP has four layers: network interface, internet, transport, and application.
  • Client/server computing underpins the Web; cloud computing lets firms rent servers instead of owning them.
  • Nepal’s Internet grew from dial-up to FTTH and mobile broadband led by NT, Ncell, and private ISPs.

Exam-Style Questions

Short answer

  1. What is packet switching?
  2. List the four layers of the TCP/IP model.
  3. Distinguish between IPv4 and IPv6.
  4. What is client/server computing?

Long answer

  1. Explain the key technology concepts behind the Internet: packet switching, TCP/IP, and client/server computing.
  2. Compare circuit switching and packet switching, and explain why packet switching suits e-commerce.
  3. Describe the development of the Internet in Nepal and its current challenges.