Communication & Information Technology (IT)

Role of Communication and IT

Communication is the process of sending and receiving information between two or more entities. Information Technology (IT) encompasses the use of computers, storage, networking, and other infrastructure to manage and exchange electronic data. In modern systems, IT infrastructure is essential for managing, routing, and processing the massive amounts of data exchanged globally.

Communication Process

The basic communication process involves seven key steps:

1. Sender: The source of the message.
2. Encoding: Converting the message into a transmittable format (e.g., binary data).
3. Channel/Medium: The physical path (e.g., wire, airwaves).
4. Noise: Any interference that can distort the message.
5. Decoding: Converting the encoded message back into a recognizable format.
6. Receiver: The destination of the message.
7. Feedback: The receiver’s response.

Communication Types & Protocols

Communication Types (Directionality)

• Simplex: Data flows in only one direction (e.g., broadcasting).
• Half Duplex: Data flows in both directions, but only one direction at a time (e.g., Walkie-Talkie).
• Full Duplex: Data flows in both directions simultaneously (e.g., telephone call).

Communication Protocols

A protocol is a set of rules and standards that govern how data is transmitted and received between devices. The format and timing of data exchange are defined here.

Examples: TCP/IP, HTTP, SMTP.

Serial and Parallel Communication

• Serial Communication: Bits are sent one after the other over a single line (e.g., USB, Ethernet).
• Parallel Communication: Bits are sent simultaneously over multiple lines (e.g., older printer ports).

Communication Channels (Media)

These are the physical pathways for data transmission:

• Twisted Pair Cable: Copper wires twisted together to reduce interference (crosstalk). Common in LANs (CAT5/6).
• Coaxial Cable: Central conductor, insulator, braided shield, and jacket. Used for cable TV and older networks.
• Fiber Optic Cable: Transmits data using light pulses through glass strands. Offers extremely high bandwidth and long distance capability.

Modems and Network Connections

Modem: Working and Characteristics

A Modem (Modulator-Demodulator) converts digital computer data into analog signals for transmission (modulation) and vice versa (demodulation). Key characteristics include speed (bps).

Types of Network Connections

Types of Networks & LAN Topologies

Types of Networks

• LAN (Local Area Network): Limited geographical area (e.g., office, home).
• MAN (Metropolitan Area Network): Spans a city or large campus.
• WAN (Wide Area Network): Spans large areas (connecting cities/countries).
• Internet: The global system of interconnected networks.
• VPN (Virtual Private Network): Extends a private network securely over a public network.

Topologies of LAN

The physical or logical arrangement of the network:

• Bus: All devices connected to a single main cable (backbone).
• Ring: Devices connected sequentially, forming a closed loop.
• Star: All devices connect to a central hub or switch (most common).
• Mesh: Every device connected to every other device (high redundancy).
• Tree: A hierarchical combination of bus and star topologies.

Components of LAN

Key hardware and software components:

NIC (Network Interface Card)

Hardware that allows a computer to connect to the network.

NOS (Network Operating System)

Software that manages network resources (e.g., file sharing, security).

Hub

Broadcasts all incoming data to all connected devices.

Switch

Directs data only to the intended destination (more intelligent than a hub).

Router

Connects different networks and routes data packets using IP addresses.

Repeater

Regenerates and amplifies signals for long-distance transmission.

Internet and Telecommunication Value

Internet: Evolution and World Wide Web

The Internet began as ARPANET and adopted TCP/IP. The World Wide Web (WWW) is an information system on the internet accessed via protocols like HTTP.

Business Value of Telecommunications

Essential for global reach, e-commerce, real-time collaboration, and operational efficiency across supply chains.

Telecommunication Systems in Nepal

The landscape is dominated by Nepal Telecom (NTC) and Ncell, with increasing adoption of Fiber-to-the-Home (FTTH) and expansion of 4G (with emerging 5G) services.

Convergence of Technologies

The blending of voice, video, and data over a single IP network, and the merging of device functionality (e.g., smartphones).