IBCSHL

Stakeholder

Individual or group affected by or with an interest in a system’s development, deployment, or operation.

Software as a Service (SaaS)

Web-hosted software accessed online; provider handles all maintenance, updates, and infrastructure.

Change Management

Structured plan for introducing new systems through training, communication, and stakeholder involvement.

Parallel Running

Simultaneously operating legacy and new systems to compare outputs and ensure accuracy before full switch.

Pilot Running

Limited trial of a new system in one department or user group to detect issues before organization-wide rollout.

Direct Changeover

Immediate replacement of the old system with the new one at a predetermined time, minimizing overlap.

Phased Conversion

Gradual implementation of system components in stages, reducing risk by limiting each change’s scope.

Data Migration

Process of transferring, mapping, cleansing, and validating data from an old system to a new one.

Testing Strategy

Comprehensive plan outlining unit, integration, system, and user-acceptance tests to verify functionality.

User Documentation

Guides and manuals that explain system features, workflows, and troubleshooting for end users.

Training Methods

Techniques (e.g., workshops, tutorials, e-learning) used to teach users how to operate the new system.

Data Backup

Regular copying of data (full, incremental, differential) to secure storage to prevent loss.

On-Premises

System hosted locally by the organization’s own servers.

Cloud

System hosted by a third-party provider and accessed over the internet.

Arithmetic Logic Unit (ALU)

CPU component performing arithmetic and logical operations.

Control Unit (CU)

CPU part that decodes instructions and orchestrates data flow between registers and ALU.

Register

Small, fast storage location in the CPU that holds instructions, addresses, or data temporarily.

MAR (Memory Address Register)

Holds the memory address for read or write operations.

MDR (Memory Data Register)

Contains the data being transferred to or from memory.

Fetch–Decode–Execute Cycle

Sequence where the CPU retrieves an instruction, decodes it, executes it, then stores results.

Data Bus

Carries actual data between CPU, memory, and peripherals.

Address Bus

Carries memory addresses specifying where data should be read or written.

RAM (Random Access Memory)

Volatile read/write memory for active processes.

ROM (Read-Only Memory)

Non-volatile memory containing permanent firmware or boot instructions.

Cache (L1, L2, L3)

Hierarchical small, fast memory close to the CPU to speed up access to frequently used data.

Persistent Storage

Non-volatile secondary storage (e.g., HDD, SSD) that retains data when power is off.

Boolean Operator

Logic gate function (AND, OR, NOT, NAND, NOR, XOR) evaluating true/false.

Logic Circuit

Network of logic gates implementing Boolean functions.

Truth Table

Tabular representation showing outputs for all possible input combinations to a logic circuit.

ASCII

7-bit encoding standard for 128 characters.

Unicode

Variable-length encoding supporting over a million code points for global scripts.

LAN (Local Area Network)

Network covering a small geographic area, like an office.

WAN (Wide Area Network)

Network spanning large geographic areas, such as multiple cities.

VLAN (Virtual LAN)

Logical segmentation within a LAN to separate traffic into distinct broadcast domains.

Router

Device that directs packets between different networks based on IP addresses.

Switch

Device that connects devices within a LAN using MAC addresses to forward frames.

OSI Model

Seven-layer framework for network design; Layer 4 (Transport) provides host-to-host communication via TCP/UDP.

Transport Layer

Ensures reliable end-to-end data transfer and error recovery (TCP) or supports faster, connectionless transfer (UDP).

Proxy Server

Intermediary that forwards requests, caches responses, and filters content on behalf of clients.

VPN (Virtual Private Network)

Encrypted connection creating a secure tunnel over public networks.

IPv4

32-bit addressing scheme offering ~4.3 billion unique addresses.

IPv6

128-bit addressing scheme supporting a vastly larger address space.

Tunneling

Encapsulating one protocol within another to secure data or cross incompatible networks.

DNS (Domain Name System)

Translates human-readable domain names into IP addresses.

Packet Structure

Data unit comprised of Header (control info), Payload (user data), and Trailer (error-checking).

Packet Switching

Sending data in discrete packets over shared network paths.

Circuit Switching

Establishing a dedicated path for the duration of a communication session.

TCP (Transmission Control Protocol)

Connection-oriented protocol providing reliable, ordered delivery.

UDP (User Datagram Protocol)

Connectionless protocol offering low-latency transmission without guaranteed delivery.

Flow Control

Mechanisms (e.g., windowing) to prevent sender from overwhelming receiver or network.

Lossy Compression

Reduces data size by discarding some information (e.g., JPEG).

Lossless Compression

Reduces size without losing any original data (e.g., ZIP).

Wi-Fi

Wireless LAN technology for local connectivity.

Bluetooth

Short-range wireless technology for WPAN.

Li-Fi

Wireless communication using light.

WiMAX

Metropolitan-area wireless broadband.

WEP

Obsolete wireless encryption protocol.

WPA/WPA2

Current wireless security protocols with stronger encryption.

Algorithm

Ordered set of steps to solve a problem or perform a task.

Sub-Procedure

Named block of code performing a specific function, improving modularity.

Abstraction

Reducing complexity by focusing on main ideas and hiding details.

Boolean Expression

Combination of variables and operators evaluating to true or false.

Two-Dimensional Array

Grid-like data structure accessed by row and column indices.

Concurrent Processing

Execution of multiple tasks or threads overlapping in time.

Pre-Condition

Condition that must be true before code execution.

Post-Condition

Guaranteed state after code execution.

Exception Handling

Techniques for catching and managing runtime errors gracefully.

Flowchart

Diagrammatic representation of algorithm steps and decision points.

Stack

LIFO data structure where push adds to top and pop removes from top.

Queue

FIFO data structure where enqueue adds to rear and dequeue removes from front.

Priority Queue

Structure where elements are dequeued based on priority rather than order.

Circular Queue

Fixed-size queue where the end wraps to the front when space is free.

Linked List

Sequence of nodes, each with data and pointer(s) to other nodes.

Binary Search Tree (BST)

Ordered tree structure where left child < parent < right child.

Tree Traversals

Inorder (L→Root→R), Preorder (Root→L→R), Postorder (L→R→Root).

Recursion

Technique where a function calls itself with smaller input until a base case.

Big O Notation

Notation describing time/space complexity as input size grows.

Bandwidth Allocation

Assigning network capacity to applications to maintain performance.

Paging

Dividing memory into fixed-size blocks for efficient management.

Virtual Memory

Using disk space to extend RAM, allowing larger programs to run.

Print Spooling

Queueing print jobs to allow CPU to continue other work.

Virtualization

Creating virtual instances of hardware or OS environments for isolation.

Centralised Control

Single controller processes inputs and drives outputs for the whole system.

Distributed Control

Multiple controllers that process inputs and coordinate outputs independently.

Sensor

Device that measures physical quantities (e.g., temperature).

Actuator

Component that converts control signals into physical actions.

Open-Loop System

Control without feedback; input is not adjusted based on output.

Closed-Loop System

Control with feedback; output is measured and used to adjust input.

Fault Tolerance

System’s ability to continue operating despite component failures.

Autonomous Agent

Independent unit that makes decisions based on local data in a distributed system.

Class

Blueprint defining attributes and methods.

Object

Instance of a class with specific attribute values.

Encapsulation

Restricting access to internal data via private attributes and public methods.

Inheritance

Mechanism where a subclass acquires properties and methods from a parent class.

Polymorphism

Ability for different classes to respond to the same method call uniquely.

Abstract Class

Class that cannot be instantiated and may include both implemented and abstract methods.

Interface

Definition of methods without implementation that classes must implement.

Composition

Building complex objects by including instances of other classes rather than inheriting.